Plasma Redshift and the Astrophysics of the Non-Exploding Universe

If there is a mechanism by which light is redshifted as it passes through low density plasma, then the implications for astrophysics are revolutionary.

I point to Ari Brynjolfsson's and Thomas Smid's theories, describe my own tentative hypothesis and discuss the explanatory power such a mechanism would have.  I also discuss cosmology, the failure to fine the Transverse Proximity Effect (#TPE) with a "foreground" quasar, and many other things.

I apologise for the length of this page.  One day I will write a whole bunch of fresh material, with better organisation.

Note: this project is currently simmering

2009 February 5:  I have a new theory of the heating mechanism - a subtle classical effect which should work best with hot plasma and which involves no esoteric physics.  It will probably take me a few years to work out a proper mathematical model and computer simulation for it.  I am also doing my best to understand Planck's black body radiation work, and what Einstein made of it in 1905 and 1917.  A paper "Planck, the Quantum, and the Historians" by Clayton Gearhart is a great place to start, I think. This involves thinking about Boltzmann's work too.  (A link farm of important early physics papers: )   Added link to some papers by B. N. Dwivedi which contain critiques of the conventional magnetic wave theories of coronal heating.

2008 November 5:  
Added some notes about the probably mistaken nature of my critique of the Ellision et al. paper in the Transverse Proximity Effect section mentioned below.
2008 November 3:  #TPE Linked to new paper failing to find the Transverse Proximity Effect for a foreground quasar in 130 QSO pairs and to another paper from 2007 on the SDSS 1115+4118 close pair of QSOs.  There is lots I would like to update on this page, and in this site, but I don't have the time to do it properly in the foreseeable future.  I have a tentative hypothesis of a sunlight-driven coronal heating mechanism.  It will take me a long time to mathematically describe it and run computer models to see if explains the observations.

2007 January 23:
I updated a section of this page which was erroneous.  The new figures for density and inter-particle spacing are here: #spacing .

In November 2005 I have an early version of what I think may be a complete redshift mechanism.
  In September 2006 I roughly estimated the acceleration of an ion, due to sunlight at 1AU, which would be required to explain the acceleration of the solar wind due to radiation pressure. For recent developments please see:
Please also see:
Earlier versions of this page can be found at*/ .  

Discussions and recent developments

Update 2004 November 8:

Be sure to look at discussions earlier in 2004, and continuing now with discussion of supernovae light curves, on the Usenet newsgroup sci.astro.research: .  Also, there is some new material I haven't checked out on  tired light and the Hubble constant: .

I have a lot more to think and write about.  I see evidence that galaxies and their clusters are not gravitationally bound - for instance their shape and the distribution of types of galaxies is not at all consistent with orbital motion around a common centre of gravity.  Probably, the plasma-redshift of starlight heats the void IGM to such temperatures that the pressure creates the voids, corralling the galaxies into their "inter-bubble"-like groups.  This raises the question of how a galaxy could be pushed by anything at all - such as very thin plasma.  This leads to the question of how a star could be pushed - since it is ejecting plasma due to some plasma-redshift light-driven motion (or conventionally, some MHD-like process), and it is difficult to see how, at least in the case of plasma-redshift, the slower motion and greater density of gas on one side of the star (due to pressure of a large external cloud of plasma or gas) could ever result in greater force in one direction on the star itself.  I propose that the visible stars are gravitationally bound to a much larger mass of black dwarfs (the remains of dead stars, from probably hundreds of billions of years) which break, by collisions, into smaller chunks.  Somehow, perhaps, these chunks and any gravitationally bound gas surrounding them collectively have sufficient wind-resistance to be pushed aside by the void IGM.  The void IGM may be at 440 Mega K.  What density would it have to be to produce sufficient sideways force on an object the size of a galaxy (actually, the black dwarf cloud is probably 2 or 4 times the visible diameter) to be of the same scale as the gravitational forces between galaxies in clusters?  Do galaxies generally produce a coronal wind of plasma, which pushes outwards and keeps them, by simple gas pressure, from getting too close to other galaxies? (This goes back to the question of how this gas force couples to the massive objects: stars and black-dwarf fragments.) 

Does the preponderence of elliptical galaxies in the middle of clusters (Dressler 1980 Galaxy morphology in rich clusters - Implications for the formation and evolution of galaxies 1980ApJ...236..351D ) result from them being more gravitationally disturbed than those galaxies at the edges?  Probably.  But those at the edges, if they were in orbits around the centre of the cluster, would often be in elliptical orbits (since the clusters themselves are not generally shaped like spheres) and so would find themselves going through the dense area from time to time, so why are they not disrupted too?  I don't think they are in orbit.  I think they are all pushing each other apart, and that as the intervening (IGM) plasma gets thinner, it gets hotter and hotter due to plasma redshift heating it and due to it finding it harder and harder to radiate the heat away - thereby leading to huge bubbles which fill most of the Universe, with galaxy clusters pushed into in the gaps between the bubbles.

I think that plasma redshift may explain the heating of the Earth's thermosphere once it becomes thin enough to create such redshift with the Sun's light. ( ) I plan to look at the conventional explanation for the heating (UV ionization of oxygen) and acceleration away from the Sun of this part of the extended atmosphere.   Perhaps a spacecraft experiment could show that sunlight affects the plasma there to heat and accelerate it, rather than the acceleration being caused by pressure of the solar wind (which itself is not well explained).  A long wide tube (like a concertina) with a window at one end could rotate to let sunlight enter along its length, with measurement of the flow, temperature and pressure of the enclosed plasma.  Is that consistent with conventional explanations, and does filtering out the UV change it dramatically?  If not, then maybe it is evidence of plasma redshift. 

(Below updated 2004 July 9.)

Starting on 2004 May 10 there has been some discussion of Ari Brynjolfsson's theory and mine on Usenet newsgroup sci.astro.research:  Specifically, this thread .  There is also some discussion on time dilation of supernovae and gamma ray burster (GRB) light curves in other threads.

There is a lot of excitement about a paper by Jerry W. Jensen:
Supernovae Light Curves: An Argument for a New Distance Modulus
>>>>  <<<<  2004 April 6
He contends that the conventional interpretation (such as by the Researchers at the Supernovae Cosmology Project of supernovae light curves is flawed.  His argues that his corrections to the conventional analysis show that there is there is no time dilation - and therefore no reason to believe the Universe is expanding according to the Big Bang Theory.  He offers an explanation of the cosmological redshift with a theory known as CREIL - Coherent Raman Effects on Incoherent Light.  But maybe a plasma redshift theory could explain it to.

This paper refers to "Malmquist Type II Bias" which is explained in a 1997 paper by P. Teerikorpi. (See especially page 109 and the example near the bottom of page 112.)
Observation Selection Bias Affecting the Determination of the Extragalactic Distance Scale
An earlier paper by Jerry Jensen and Jacques Moret-Baily explains CREIL:
Propagation of electromagnetic waves in space plasma  2004 January 25

There is a lively discussion of Jerry Jensens' paper at .  Check Jerry's posts there for such discussions, such as  "Against the Mainstream: Cutting the Cord on the Big Bang" and an earlier one "Bad Supernova Data Reduction" .   Another forum where CREIL is: - Jacques Moret-Baily participates as JMB.  Search for other references: .

I joined the first discussion and pointed out that the failure to find the Transverse Proximity Effect with a foreground quasar is another reason to believe that the Lyman alpha forest and most of the redshift of quasars happens in their immediate vicinity, as Jerry suggests.  A good argument for this is - as best I know - the absence of Lyman alpha forest in the spectra of high redshift galaxies and most (or all?  Bill Keel told me some have it) BL Lac objects.  In the later case, I guess the light we see comes mainly from the lobes and a lot of the redshift of the core of the quasar occurs in the radius around it typically less than the lobe radius - so we don't see lobes being redshifted as much as cores.

Ari Brynjolfsson has published a second paper - with a new analysis of supernovae light curves, according to his plasma redshift theory, again showing no time dilation.
Plasma Redshift, Time Dilation, and Supernovas Ia  2004 June 19
He also rejects the notion of his plasma redshift theory being a tired light theory - but I have classed it as such in this web-page, because I believe the "tired" refers to each individual photon losing energy. 

One of several papers by David G. Russell suggests that some types of galaxies have intrinsic redshift, or more intrinsic redshift than others:
Intrinsic Redshifts in Normal Spiral Galaxies  2003 October 10

See a later paper: .
An open letter to the scientific community regarding the way researchers who challenge the Big Bang Theory are marginalised or suppressed: .  Also, a page which says that this letter was rejected by Nature, before eventually being published in New Scientist: .

2004 May 12
  Robin Whittle 

An update history is at the end of this page.  This page grew in several stages from 2003 October 23, and so its structure is a mess - but no-one could accuse it of lacking ambition!   I intend to completely rewrite this material as many separate pages. 

To the main page of this site: ../.  To my main website:


>>> Introduction and synopsis

>>> Link to Ari Brynjolfsson's paper

>>> Contact, copyright etc.

>>> The expanding Universe and the Big Bang theory

>>> Non-Doppler redshift theories - "Dimple" redshift

>>> Coronal heating and solar wind acceleration
>>> Spicules
>>> Prominences
>>> Energy and mass of light encountered by each particle close to the Sun
>>> Dramatic events in the transition region?
(New 2004-04-27.)
>>> Coronal heating and solar wind acceleration - how much energy is required? (New 2004-04-27.)
>>> Why isn't the required redshift observed? (New 2004-04-27.)
>>> Revisiting Free-Free Absorption?

>>> Combining the catalogues of the 2dF surveys

>>> The Cosmic Microwave Background radiation and black dwarfs

>>> Plasma redshift, the Inter Galactic Medium, Voids and Galaxy Clusters
>>> The X-Ray Background Radiation
>>> The Void and Cluster IGM
>>> Large scale structure of the Universe
>>> Galaxies, AGNs and Quasars
>>> The "Finger of God" effect
Researching galaxy redshift scatter (New 2004-05-10.  Low-key, probably best to skip it.)

>>> Ari Brynjolfsson's Plasma Redshift theory
>>> Thomas Smid's Plasma Redshift theory
>>> Theories which may be related to plasma redshift

>>> The Quasar - Quasar Transverse Proximity Effect

>>> Coronal / Solar Wind Element Fractionation: the FIP Effect
>>> Fast and slow wind velocities
>>> Fractionation of low FIP elements - does plasma redshift play a role?
>>> Different rates of FIP fractionation for different elements
>>> Different fractionation factors for slow and fast winds

>>> Laboratory tests of plasma redshift and the role of light in low-FIP fractionation

>>> Astronomy and Astrophysics Resources and Links

>>> Update history

Introduction and synopsis

I propose a theory of plasma redshift in a qualitative and broadly
theoretical manner - and explore its implications.  I point to Ari
Brynjolfsson's highly mathematically developed theory - which predates
and differs in some important respects from mine.  I also propose some
indirect lab tests for my plasma redshift process, including of
sunlight's role in the fractionation of low-FIP elements in the

If there is a mechanism by which light is redshifted as it passes
through low density plasma, then the implications for astrophysics are
revolutionary.  Plasma redshift could explain a number of phenomena
which are currently not fully understood or which are explained in ways
which contradict other observations or established principles.  Such
phenomena include:

  The heating and acceleration of the solar corona and wind,
  including the rapid onset of heating in the transition
  region.  (Once the material is ionized and reaches a density low
  enough that the average inter-particle spacing creates an
  inhomogenous medium for the wavefronts of photospheric photons.)

  Likewise in other stars.

  Low-FIP fractionation of elements in the chromosphere.

  Increased redshift of photospheric lines when observed near the
  solar limb.  (The light passes through a greater quantity of
  coronal plasma - but there are also likely to be other factors
  in the limb-effect and other variations of redshift across the disc.)

  Halos of hot, thin, plasma around galaxies and galaxy clusters.

  Hot stars, apparently, having higher redshifts than expected.

  Some, most or perhaps essentially all of the redshift of galaxies
  and quasars.  (Through the IGM redshifting light about 1 part in
  13,000,000,000 per year of travel, with higher rates of redshift
  for areas with denser plasmas, such as around quasars.)

  "Finger of God" redshift anomalies in areas with densely packed
  galaxies.  (Due to generally higher densities of IGM for significant
  distances in those clusters.)

  The failure to find the Transverse Proximity Effect with a
  foreground quasar.  (Due to the early part of their Lyman alpha
  forests being caused by neutral H clouds close to each quasar, and
  their distances from Earth being much closer than conventionally
  assumed - and not a direct function of their total redshift.)

  Likewise the rapid variation of quasars, which is impossible to
  understand according to the conventional Big Bang interpretation
  of their redshifts, which results in such large distances and
  therefore such immense luminosities that an object small enough
  to exhibit such rapid changes would exceed conventional limits
  of energy density: the "Compton catastrophe".

  The relative absence, as I understand it, of Lyman alpha forests in
  the spectra of BL Lac objects.  (Perhaps due to the observed light
  being from the end of a quasar's jet, where it meets the lobe, with
  the jet pointing directly towards us and the quasar core hidden by
  the lobe and jet, whilst quasar Lyman alpha clouds are typically
  clustered in concentrated IGM which does most of the quasar's
  redshift close to the core.  Those clouds would be either generally
  closer to the quasar than the lobe and/or found less often directly on
  the other side of the lobes from the core of the quasar.)

  The X-ray background radiation and the very low level of neutral
  H, or absorption in general, in the IGM.  (Due to the IGM being
  heated to hundreds of Mega Kelvin by the redshift of starlight and
  so attaining a very low density.)

  The Sunyaev-Zeldovich effect.  (Due to the 2.7K microwaves from
  distant galaxies being redshifted in the IGM behind, and to some
  extent within the cluster, and being mixed with the non-redshifted
  2.7K microwaves produced in and around the cluster's own galaxies.
  Read on for this theory of galaxy halos of black dwarfs emitting the
  CMB - and being the dark matter required for observed stellar motion
  around spiral galaxies.  This seems feasible if the Universe is
  vastly older than 15 billion years.)

  Apparent elemental abundances of high redshift quasars, which in the
  Big Bang theory are regarded as extremely distant and having
  radiated the light we see not long after the Big Bang, having
  quantities of heavier elements not much different from our Sun. (This
  is inexplicable in the Big Bang theory, which has heavier elements
  made by stars from hydrogen, at a presumably rather slow rate, and
  elements heavier than iron made only in supernovae.  If plasma
  redshift shows
the Universe is not expanding and so is probably
  exceedingly old,
then the quasars are seen to be made of material
  which has had a long
time to be synthesised.  Also, high redshift
  quasars are shown not to
be so far away and old as currently

If plasma redshift is found to exist, then I believe that it would
probably account for the great bulk of the redshift of galaxies
and quasars - which is conventionally attributed to Doppler shift as a
result of the "expanding Universe".  If so, then the Big Bang theory
would need to be abandoned, or at least remade with an immensely
longer timescale (the Big Old Bang?) - since it would probably be
concluded that no significant expansion of the Universe is observed
at present.

If one or more of these plasma redshift theories are shown to be valid
and can explain most of the redshift of distant objects, I think that
the Big Bang theory will be replaced with a theory that the Universe is
exceedingly old and vast, and currently not appreciably expanding or
contracting.  This might be combined with the realisation that current
observational limits and the slow rate of change prevent us from
reliably theorising anything in detail about how the Universe attained
its current state.

If this happens, I propose that such a basis for astronomy be known as:

  NEU = the "Non-Exploding Universe"

Maybe the Universe *is* expanding or contracting a little - but this
terminology distinguishes the new basis from the Big Bang's notion of
recent and explosively dramatic expansion from a single point.

Science does not require that a theory be replaced in order for it to be
disproven.  A single solid disproof is all that's needed for progress to
be made.

Nonetheless it is customary and persuasive to provide a new theory as a
drop-in replacement and to use that theory as the foundation of new and
more elegant explanations for observations which were previously
explained with the old theory.

Here are some hypotheses which show that it is not hard to think of
plausible-sounding mechanisms to explain observations, once it is
accepted that the Universe is a *lot* older than 15 billion years.

The Cosmic Microwave Background radiation could be caused by a large
"graveyard" of cold collapsed stars - black dwarfs and their collision
fragments - in generally elliptical and random orbits in a roughly
spherical halo centred on each visible galaxy.  This would attain the
average (black body) temperature of space (2.7 K) and "radiate the CMB".

In this hypothesis, the black dwarfs would also be absorbing and
re-radiating the CMB, but their primary role would be to provide a large
distributed set of black body objects which lack internal heating.
Over time, each of these would attain the average radiant temperature of
2.7 K seen by such a body.  In order to do this, it would have to be shown
that their temperature is relatively unaffected by the plasma they are
bathed in.  They would gravitationally retain or attract an atmosphere
of higher density material which is not subject to plasma redshift
heating, which could be quite cool and would insulate the black dwarfs
from the surrounding galactic coronal plasma.

This 2.7K temperature would be an average of the hot starlight, and a
few AGNs and quasars, over very small solid angles, plus the CMB and
other types of background radiations, averaged against the generally
dark sky.  The question of the generally darkened nature of distant
space, in what may prove to be an effectively endless Universe, is
Olber's Paradox.  Perhaps the darkening is caused primarily by dust,
these black dwarfs and plasma redshift.  This is just darkening in the
visible wavelengths - when viewed with microwaves, the sky is bright,
from all these "black" dwarfs and their collision fragments.

Such a halo of black dwarfs could constitute the the missing mass needed
to explain orbital motion in spiral galaxies - without the need for
exotic states of matter.  They should be detectable as MACHOS, if they
are big enough.  But perhaps, over time, they have collided and smashed
into pieces which are too small to detect via gravitational lensing.
The fragments around our own galaxy may generally subtend a smaller
angle from Earth than the stars in nearby galaxies, so we may not see
much evidence of them via occultation of those stars.

The large-scale structure of the Universe, with its huge bubble-like
voids with galaxy clusters corralled between them, has no obvious
explanation in the Big Bang theory.  This pattern of arrangement of
matter is in stark contrast to the gravitationally driven circular
orbital patterns found in solar systems and galaxies.  Plasma redshift
provides a fruitful basis for explaining this structure - the apparent
ability of vast, very low density, sections of the Universe to push
everything else together in a way which seems to have little to do with

The X-ray background radiation, according to some researchers, is only
explicable in terms of the Void IGM being extremely hot - they estimate
440 Mega K.  There is no obvious mechanism in the Big Bang theory for
heating this medium, or any other sparse plasma, to such temperatures. 
Plasma redshift of distant galactic starlight (and probably the
background levels of radiation at other wavelengths) would heat the Void
IGM, as well as the Intracluster IGM - just as it does the coronae of
stars and galaxies.

The lower the density of a fixed volume of proton-electron plasma - say
a cubic metre - the hotter it has to be to get rid of a certain amount
of energy by radiating it as electromagnetic radiation, such as UV,
Extreme UV (EUV) and X-rays.  At temperatures above a million Kelvin,
this radiation is primarily by the bremsstrahlung (German for "breaking
radiation") process: two charged particles passing close to each other
have their paths changed by their electrostatic attraction or repulsion -
and the result is that energy is emanated in what we regard as a single

Below a critical density (such as an interparticle spacing of about 5
microns for starlight) plasma redshift's ability to deliver energy to a
cubic metre of plasma scales linearly with the density in particles per
cubic metre.  The cubic metre of plasma's ability to radiate heat via
free-free emission (bremsstrahlung) scales with the plasma's density

So for a given flux of light - such as background starlight from distant
galaxy clusters - the lower the density of a cubic metre of plasma, the
greater the ratio between the energy it absorbs via plasma redshift and
its bremsstrahlung emission of energy at any given temperature.
(Bremsstrahlung emissivity is proportional to the temperature in
relativistic plasmas - or to the square root of the temperature in
thermal plasmas.)

Since the starlight flux is fixed, an unconfined plasma in this setting
would continue indefinitely to heat up and expand to a lower density.
Typically, a limit would be imposed by pressure at the boundaries of the
voids.  (Perhaps part of the equilibrium would be matter synthesis
within the void plasma due to it being relativistic, and the particle
collisions have sufficient energy to create matter in the form of
an electron-positron pair.  The positron is the positively charged
antiparticle of the electron, and is usually regarded as being
identical but opposite - but some recent research suggested they have
differing properties.  Perhaps this matter creation feeds the Void IGM -
making it partly or wholly a plasma of positrons and electrons, rather
than the electrons, protons and other nuclei we expect if it is made
of ordinary matter.)

This constant heating and potential expansion (with or without matter
synthesis) suggests the existence of a fundamental pressure throughout
a very old Universe for all the Void IGM.  Individual voids would
attain pressures approximately the same as other voids - with the galaxy
clusters sandwiched between them and subject to that same general
pressure.  The characteristics of the inter-void strips of Intracluster
IGM, together with the gravitational and radiative effects of the galaxy
clusters which are embedded in these strips, would determine the
pressure limit for the voids.

Since starlight is fairly evenly distributed throughout the Universe, we
would expect the Void IGM everywhere to stabilise within a narrow
range of densities - and therefore temperatures and rates of plasma
redshift.  Most of the space in the Universe is filled with Void IGM.
If it was shown to exist at about the same density everywhere, then we
would expect to find a generalised correlation between distance and
redshift for objects such as galaxies which have little "intrinsic"
redshift, since most of the distance between these objects and Earth is
through the voids or through smaller volumes of plasma with similar
characteristics to the voids, but probably somewhat higher rates
of plasma redshift.

For this theory to explain the observations of most galaxies, the
Intracluster IGM and intra-galactic ISM (both of which would probably
have higher densities due to gravitational attraction, and so have
higher rates of plasma redshift per megaparsec) would have to extend for
small enough distances, in general, compared to the Void IGM, to
contribute a relatively insignificant amount of redshift
to the total we observe.  When the Intracluster IGM extends for larger
distances, such as in clusters with lots of galaxies, then we may
observe the galaxies towards the rear of the cluster via light which
has passed through enough Intracluster IGM plasma to appreciably
increase the total redshift.  Then, galaxies on the far side of the
cluster would have a significantly higher redshift than the galaxies on
our side - which would be a component, in addition to genuine galaxy
velocities, of the "finger of God" effect.

The "intrinsic" redshift of high redshift quasars, if explained with
plasma redshift, would probably occur due to them gravitationally
concentrating IGM around them to high enough densities, over long enough
distances, so that most of the redshift we observe in their light occurs
over distances close to the quasar which are small compared to their
distance from Earth.  If this proves to be the case, then most of a
typical quasar's redshift is local to the region near its black hole
core, so we can't use their total redshift to determine how far away
they are.

In this view, quasars may not be located in conventional galaxies -
because we would expect to see any such galaxy, since quasars are
probably generally no more distant than other galaxies.  In the absence
of a conventional galaxy around a quasar, there could be a simple
concentration of IGM falling into the accretion disk or whatever
radiationally and gravitationally determined structures surround the
disk.  Perhaps some star formation could occur in this concentration.

I imagine some kind of balance developing between gravitational
concentration of IGM and radiation pressure (partly or largely due to
heating and momentum deposition in the plasma as quasar radiation is
plasma redshifted) such that very large volumes of space (such as the
size of an average large galaxy) around the quasar are filled with a
higher than usual concentration of plasma.  This may be detectable via
statistical analysis of the redshift of galaxies which are near to
quasars in the sky plane, since some of those galaxies (or parts of the
one galaxy) would be observed with light which passes through the
quasar's local zone of concentrated IGM.

If there is such a cloud of redshifting plasma around the core (black
hole, accretion disk etc.) of a quasar or radio galaxy, then we would
expect the cloud's redshift, which presumably increases with density
closer to the core (until the inter-particle spacing is too small for
a particular wavelength and coherence length of light, or microwaves)
to make it harder to observe the part of a jet near the core.  This
would be true when the jet is coming towards us or when the one or two
jets are approximately perpendicular to our line of sight.  This effect
of increased redshift shrouding of the core ends of the jets, as well
the vastly more luminous core, would generally be more important at
optical wavelengths than with microwaves, since plasmas with
inter-particle spacings such as 0.01 to 10 mm (a billion to one range
of densities) will redshift light but hardly affect the microwaves used
in the VLBI observations with which jets and lobes are normally

Similarly, the obscuring effect of such a cloud of redshifting plasma
could also be invoked, in addition to relativistic dimming, to explain
why we rarely or never observe a jet at visible wavelengths when the jet
is pointing away from our line of sight.

Perhaps some or many quasars are in the voids - if they exist separately
from, or have been ejected from, galaxy clusters.  I explore what might
be called "the aerodynamics of plasmas, stars, galaxies, black holes and
black dwarfs and their collision fragments - and the collision and
close-encounter ballistics of all these objects".  This may be a
starting point for understanding how visible galaxies and their black
dwarf halos are confined in a larger and potentially more massive body
of Intracluster IGM - with this and its constituent galaxies being
confined by the Void IGM as well as being subject to their own
gravitational self-attraction.

A plasma redshift theory predicts redshifts in the transition region and
corona of stars.  (An exception would be Wolf-Rayet stars.  One line of
investigation is to look at what may be a lack of EUV and X-ray emission
from their outer atmospheres - what in lower wind stars would be a
corona, but which in a WR star may be too dense to be heated by plasma
redshift.  WR winds are, as best I know - and I have only read a little
about them - driven by radiative deposition of inertia from light which
is absorbed by the heavy elements in the wind.  The high density of the
wind keeps it relatively cool too.)

If plasma redshift does provide most of the energy for the heating and
acceleration of the transition region, corona and solar wind, then
we should expect an average redshift of 3 or more parts per million.
Active regions and specific structures within those regions, if
powered primarily by plasma redshift, would be expected to show a
somewhat higher redshift of the photospheric light travelling through
them.   However, we cannot measure such small redshifts of the Sun's
Planckian black body curve - we can only measure the shift of lines,
primarily absorption lines.  It may be thought that no such shift
is observed.  I discuss how a plasma redshift process might be
shifting the continuum light by 3 or more parts per million, or
much higher in some active regions, whilst not appreciably shifting
the absorption lines, which are highly resonant and involve a
coherence length much longer than is likely to be redshifted in
the transition region or corona.

I propose that quasar redshifts are caused by a region of concentrated
IGM around them - so it might be expected that similar objects, such as
the black-hole radiant cores of Seyfert galaxies also be surrounded by
such a redshifting body of plasma.

However, we find (as best I know) no significant observable redshift
differences between Seyfert galaxy cores and the stars in those galaxies. 
(Such an observation would show that quasars etc. have intrinsic
redshift.  Researchers who accept the Big Bang as fact rather than theory
- as many seem to - might be tempted to ignore or doubt any such

Assuming a continuing genuine absence of differing observable redshifts
between Seyfert galaxy cores and stars, then for a plasma redshift
hypothesis to withstand scrutiny, such galaxies would need to be shown
to contain insufficient integrated {distance of redshifting plasma x
density of redshifting plasma} to create observable differences between
the absorption and emission lines of light from the core and from the
stars on the periphery of the galaxy.  Exactly how this could occur,
and how neutral hydrogen clouds could exist in the IGM and especially
near quasars, are questions I haven't developed theories for yet.

Unless galaxies in general, or active galaxies in particular, could be
shown to be highly devoid of plasma which redshifts light, then the
answer must lie in the greater precision with which we can observe
redshifts in individual stars (the Sun at least) than within distant
galaxies, and in the naturally concentrated nature of redshifting
plasma close to most stars.

Many of the problems with quasars disappear once their distribution in
space is considered to be about the same as that of galaxies - with high
redshift quasars, on average, not necessarily being much further away,
or any further away, than ordinary galaxies which typically have a much
lower redshift.

For instance, the Big Bang compatible explanation for the "superluminal
motion" of quasar jets requires that many quasars have highly
relativistic jets improbably aligned very close to our line of sight.
Yet such speeds are not, to my knowledge, typically found in jets
emanating from Seyfert black hole cores when there are two visible jets
(which shows they are probably not aligned close to our line of sight)
and which are in galaxies we can see in sufficient detail to make a
reasonable estimate of distance, irrespective of their redshift.

The Big Bang estimate of many quasar distances are arguably far in
excess of their real distance, since these large distances lead
to the requirement that their energy output is so prodigious as to
vastly outshine the largest galaxies, and violate the reasonable
sounding physical principles concerning self-absorption.  This is the
"inverse-Compton catastrophe" - where "catastrophe" is the fate of any
theory which requires that a body of a certain size radiate energy at a
rate beyond the predicted limit.

Similarly, the rapid variation in the radiation of quasars, at all
wavelengths but especially in the UV and X-ray ranges, is a powerful and
I think conclusive argument that in order to remain compatible with
known physics, their output powers, and therefore their distances, must
be smaller than those calculated according to Big Bang cosmology.

Likewise, conventional Big Bang interpretations of redshift lead to
distances for quasars and radio galaxies so extreme that the computed
sizes of their jets and lobes may exceed the size of galaxies by
factors which are hard to believe.

But these problems are with the Big Bang theory - it is much easier to
explain quasar observations once it is decided that a lot of the
redshift of high redshift quasars (and probably some galaxies too)
occurs very close to them.

Plasma redshift may not turn out to be the correct explanation for all
this redshift, heating and acceleration of plasmas - but a process
resembling this has tremendous explanatory power.  The vast edifice of
sophistication, precision and supposed certainty which has accreted onto
the Big Bang theory is rendered either irrelevant or in need of complete
reappraisal if it can be shown that light can be redshifted by low
density plasma - or by another physical thing, such as, a flux of
neutrinos or more exotic particles.

I hope that this page stimulates thought and discussion.  If just one
of its proposals stimulates the development of better theories, then
I will be happy. 

I think solar physics has been stuck for 40 years on the question of
the heating and acceleration of the transition region, corona, active
region structures and wind.  (Meanwhile, look at the progress in
other feilds of astronomy and in spaceflight, telescopes,
semiconductors and computers!)  While I think great progress has been
made on the Sun at and below the photosphere, our knowledge beyond
about 2,000 km above the photosphere is limited.  All the observations
and theories about active region structures are taking place in a kind
of limbo of non-understanding the heating and acceleration mechanisms
- like studying forest fires without really understanding combustion. 

The Big Bang explanation of quasars is obviously wrong - they can't
be as distant, and therefore as intrinsically luminous as
conventionally thought.  There are too many contradictions, so I am
sure that Big Bang cosmology is wrong in this respect, and so
probably in all other major respects as well. 

I don't know if all the theories presented here are novel.  As far as I
can tell with Google, there are currently (April 2004) exactly two
theories of plasma redshift - Ari Brynjolfsson's theory (which he has
been developing since 1978, but only published fully in January 2004)
and mine, such as it is.  Paul Marmet's redshift theory for neutral
hydrogen theory prompted me to develop my own, starting in late 2002.

(Note added 2004-05-10:  Perhaps there is redshift in vacuum from
 the particles supposedly created by vacuum energy - but where would
 the energy go?)

I am a newcomer to this field and would really appreciate any help in
correcting errors in this page and improving my understanding.

This is a living document.  Please contribute critiques and suggestions
- I will incorporate them with full attribution, and link to any
relevant papers, web sites and discussion forums.  I plan a fuller
exposition, with better organisation and multiple, smaller, pages!

- Robin Whittle

Ari Brynjolfsson's paper

Redshift of photons penetrating a hot plasma

was published on 2004 January 21 and revised to version 2 on 2004 March 30:   

The version 2 abstract is :
A new interaction is derived, which is important only when photons penetrate a hot, sparse electron plasma. When photons penetrate a cold and dense electron plasma, they lose energy through ionization and excitation, through Compton scattering on the individual electrons, and through Raman scattering on the plasma frequency. But when the plasma is very hot and has low density, such as in the solar corona, the photons lose energy also in a newly derived collective interaction with the electron plasma. The energy loss of a photon per electron is about equal to the product of the photon's energy and one half of the Compton cross section per electron. The energy loss (plasma redshift of the photons) consists of very small quanta, which are absorbed by the plasma and cause a significant heating. In the quiescent solar corona, this heating starts in the transition zone to the solar corona and is a major fraction of the coronal heating. Plasma redshift contributes also to the heating of the interstellar plasma, the galactic corona, and the intergalactic plasma. Plasma redshift explains the solar redshifts, the redshifts in the galactic corona, the cosmological redshifts, and the cosmic microwave background. The plasma redshift, when compared with experiments, shows that the photons' classical gravitational redshifts are reversed as the photons move from the Sun to the Earth. As seen from the Earth, a repulsion force acts on the photons. These findings lead to fundamental changes in the theory of general relativity and in our cosmological perspective.
Below I make some brief comments on this paper, including how his theory differs from mine.

Ari Brynjolfsson's papers are at:

Contact and copyright

The home page of this site is a placeholder for new and better presented expositions on these matters in the future.  Please link to that URL: or to this page . There are HTML targets in the file - as used in the Contents links - please link to these if you like.  While this page will be replaced at some stage later in the year, I will maintain this file as an archival document, and place links to where the updated material is on other pages.

To - my main First Principles site - for many other things, such as the world's longest Sliiiiiiiiiiinky - 21 metres and suspended on 418 elastic threads so it can carry waves in all three dimensions.  Also various show-and-tell things, my privacy advocacy and Internet censorship work, the Devil Fish modifications to the Roland TB-303 sequencer/synthesiser . . . and much more . . . .   To find out more about me:
Copyright 2003 - 2004 Robin Whittle    Melbourne Australia 

This site is on a server I rent from in San Francisco.

The term "Non-Exploding Universe" is not copyright! 

Please quote or reference the material here with the attribution:
Plasma Redshift and the Astrophysics of the Non-Exploding Universe
(give the date of the current version of the page)
Robin Whittle
If you find this interesting please let me know.  Please also let me know if you quote, discuss or link to this site.

I am keen to hear from anyone who wants to work on these ideas - particularly from someone with better mathematical skills than I, or with better insight into quantum mechanics, plasma physics, radiative transfer and stellar spectroscopy.

See the end of this page for an update history, and where to find earlier versions of this page.

Check the Wayback Machine to see earlier versions of this page: .  6 months after the page was established or changed, you should be able to see the earlier versions of this page from its original location*/ . After mid October 2004 the versions at this site should be available at:*/ .

The expanding Universe and the Big Bang theory

This discussion follows from another page:  of a galaxy with a redshift of 0.96 - the light we see has wavelengths 1.96 the length (we reasonably assume) it had when emitted.

Conventional astrophysical theory is that (apart from some small gravitational redshifts) the redshift is caused solely by the velocity of the emitting object moving away from us (often construed not as actual motion, but as the rather more mysterious "expansion of the Universe")  - which would be a high fraction of the speed of light, since the waves are arriving at about half their original frequency.  (It seems to be a matter of controversy how to calculate a velocity from high redshifts: . )

It is observed that in general, the further a galaxy is away from us (as estimated by various methods, including its angular size, as we have done in the just-mentioned page) that the more its light is redshifted.  This pattern is known as the "Cosmological Redshift".

The conventional "Expanding Universe" interpretation of the Cosmological Redshift is that the light from distant galaxies (and quasars) starts off at the same frequencies (and therefore wavelengths) as light here on Earth.  (Thus, it is assumed that fundamental physical constants and principles are the same in the distant galaxy as they are here now.)  The conventional interpretation is that the redshift is caused solely by the object moving away from us - other than allowances for slight gravitational redshifts as the light escapes the gravitational fields of massive objects.  If this interpretation is correct, then the Universe certainly is expanding and therefore it would be reasonable to postulate that it started with a Big Bang.

However, this conventional interpretation also involves the assumption, rarely stated, that the light is not in any way redshifted by the space it travels through.  There have been various theories as to how this could occur.  These are known as "tired light" theories, and they are almost completely discredited in the minds of modern astronomers.  If anyone knows of a good history of tired light theories, please let me know.  I have done some research, but not written it up yet.  See these pages: - recently updated discussion of Tired Light, with some references; and  Errors in Tired Light cosmology, by Edward L. (Ned) Wright.

Since about the 1920s, a tremendous effort has been made to determine the relationship between redshift of galaxies (and quasars) and their distance.  The relationship, in Expanding Universe theory, is governed primarily by the so-called "Hubble Constant", as well as various other parameters of cosmological theories, such as how the (purported) expansion of the Universe has accelerated or decelerated since the (purported) Big Bang.   (Note 2004-03-22: In 1998, Adam G. Riess et al. observed supernovae and concluded that the expansion rate was not slowing, and may indeed be accelerating.  Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant, Astron.J. 116 (1998) 1009-1038: )

There are a variety of estimates for the Hubble Constant - between 50 and 100 kilometres per second per megaparsec.  Currently fashionable values are around 70 km per second per megaparsec.  (This was refined to an apparently widely accepted 72 (+/- 5) km per second per megaparsec, in February 2003, based on a variety of observations . . . and lots of theory . . . especially the WMAP observations of the CMB anisotropy: First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Determination of Cosmological Parameters, D.N. Spergel et al, 2003, ApJS, 148, 175,   If you find the light of a distant object is redshifted by a factor of 0.000233, and assume that this is caused by Doppler shift, then its recession velocity is about 70 km/sec.  (0.000233 x 300,000 km/sec)  With the Expanding Universe theory and the "Hubble Constant" set to 70 km per second per megaparsec, then this means that the object is about 1,000,000 parsecs away from us.  (A parsec is a unit of astronomical distance based on the distance a star must be from the Sun in order for its apparent position to change by one arc second (1/3600 degree) when viewed from Earth at two extremes of our orbit around the sun.  A parsec (parallax second) is 3.26 light years, or 3.089 x 1013 kilometres.)

But suppose there was a physical mechanism by which a photon of light (and ultraviolet, X-rays, infra-red, microwaves etc.) could lose some of its energy as it travelled through the intergalactic medium.  (I think it is best to consider "photon" as a handle for what we do and don't know about how the electromagnetic force gets from one place to another.  While "photon" theory may work, I don't think there is such a thing as a photon in reality - it is just that we can talk about a photon once we have received a quantum of energy at some place at some time.  In 2003, Caroline Thompson wrote to me very concerned that I thought that photons existed.) The intergalactic medium is currently thought to be mainly very low density plasma - there's no sign that it is primarily hydrogen as atoms or molecules.

At what rate would a photon have to lose energy, on average, as it travels through the intergalactic medium, in order to give a redshift of 0.000233 per megaparsec?  (This is the same redshift as having the "Hubble Constant" set to 70 km per second per megaparsec.)

The frequency of a photon is directly proportional to its energy.  Its wavelength is inversely proportional both to its frequency and energy.

How much energy would a photon need to lose in a year of travel through the intergalactic medium in order to have this redshift?

2.33 x 10-4 per 1,000,000 parsecs

Let's convert this to light years, by multiplying it by 3.26:

7.60 x 10-4 per 1,000,000 light years

So how much energy would this be per year of travel?  Divide it by a million:

7.60 x 10-10

= 0.00000000076

= 1 /  13,200,000,000

So if there was a physical mechanism by which a photon lost one thirteen billionth of its energy by travelling through intergalactic space for a year, then this would explain the observed redshifts, without the need to think that the redshift was Doppler shift caused by movement of the object away from us.

One part in 13 billion is not very much.

If you are 31 years 8 1/2 months old, then you have been alive for a billion seconds.  (Modern CPUs do 3 billion operations per second . . . . . .  !!!!)

The Earth's diameter is 12.7 billion millimetres.

There are many problems with the expanding Universe theory, and therefore the Big Bang theory, such as it being hard to imagine the large scale structure of the Universe developing after only 15 billion years expanding from a single point.  Another major problem is quasars, which are supposedly at the edge of the Universe on account of the Doppler interpretation of their high redshifts - yet which vary their light output in hours or days, so they can't be very big, which makes no sense for something which is apparently as bright as a galaxy - or up to 100 times as bright.  (Read on about the Transverse Proximity Effect and how it indicates quasars are not at the distances derived from a Doppler interpretation of their redshift.)

The usually cited "proof" of the expanding Universe is the redshift of light from distant objects, such as the distant galaxies. I think this is the only potentially substantial reason for believing in the expansion of the Universe - but the Big Bang theory would need to be completely revised or abandoned if it could be shown that some, or almost all, of the observed cosmological redshift was caused by something other than Doppler.

The other two oft-cited pieces of evidence / argument for the Big Bang theory are explicable in many other possible ways:
These two items of "proof" are not proof at all that there was a Big Bang or that the Universe is expanding.  There are, however, some papers which supposedly show time dilation of certain types of supernova according to the apparent distance from Earth - as would be expected if the source was moving away from us with a velocity which accords with the redshift of the light we observe from the object.  If these turn out to be correct, then I would say these objects are indeed moving away from us and that therefore the Universe is expanding.  But such work relies on several rather hard-to-ascertain variables, such as the degree of extinction (absorption of light) between the supernova and Earth.  (See Banerjee et. al 2000AJ....119.2583B full text here.)

Proving that the quasars are in the same vicinity as galaxies of lower redshift, as has been suggested and indicated many times in the past (see, for instance the statistical analysis by Robert V. Wagoner, Radio Sources and Peculiar Galaxies Nature 20 May 1967, Vol 214, pages 766 to  769 - and Halton Arp: Peculiar Galaxies and Radio Sources 1967ApJ...148..321A  ) would show that there is an astrophysically important redshift mechanism which is totally unrelated to Doppler.  If such redshift mechanisms (one or more new ones) work within or around quasars, then it becomes incumbent on Expanding Universe theorists to show that such mechanisms do not occur at all in the intergalactic medium or in or around galaxies.  If there is non-Doppler redshift in the intergalactic medium, then this may explain the observed cosmological redshifts, and so there may be no reason to believe the distant galaxies are moving away from us at all.  If this is shown to be the case, then the Expanding Universe and Big Bang theories would probably be shown to be modern science's most extraordinary, persistent, aggressively defended, expensive and thoroughly misleading blunder. 

There is a fabulous set of pages on galactic evolution, and on quasars and Active Galactic Nuclei (AGNs) in particular, by Bill Keel:  - in particular the quasar and AGN page: and the essay Quasar Astronomy after 40 years: .  Also, as part of his extensive lecture notes on galaxies: is a page on the long controversy over quasars having (or not, as is the conventional view) intrinsic redshifts:   Also be sure to refer to Halton Arp's book "Seeing Red" and the work of Margaret and Geoffrey Burbidge.  The paper "Very close pairs of quasi-stellar objects." by Burbidge, G., Hoyle, F. & Schneider, P of 1997 is an important document too: .

(Can anyone point me to the VLB radio image of a radio galaxy, BLAZAR, QSO (whatever . . . ) which had two jets clearly showing switching between FR1 and FR2 modes?  Or was this just something I dreamed?)

Non-Doppler redshift theories - "Dimple" redshift

If a mechanism can be found by which a photon of light loses one part in about 13 billion (actually anything in this range would do) of its energy after travelling through the intergalactic medium for a year, then there would be no reason to think the Universe is expanding rapidly - and therefore no reason to think that there was a Big Bang. 

I am on the case with my own theory.  Two other theories are: Here is a very brief description, of what I call "Dimple Redshift", after I explained it to my friend Marcia.  She suggested that my use of the term "dent" should be changed to "dimple" - which is indeed more instructive and attractive.

When a photon with a short coherence length (as is the black-body radiation from the Sun) passes through a low density plasma (or arguably a neutral, partially ionised/ionized gas, or even molecules to very small grains of dust) it is not passing through an homogenous medium.  It travels at full light-speed in the vacuum between the particles, and then is slowed down when it encounters one or more particles.   If we imagine the wavefront being a parallel front travelling through empty space, with a single particle (say an electron, a proton, an ion, a nucleus, a molecule etc.) in its path, the wavefront is very slightly slowed down in the vicinity of that particle.  This puts a slight *dimple* in the otherwise planar (actually its the surface of a large sphere) wavefront. 

A thought experiment indicates that this, or something like it, must occur.  A plasma has a refractive index above 1.0 - it slows down light which passes through it.   No matter how low density the plasma, as long as there are some particles, the refractive index will still be above 1.0.  Therefore, even when the density is so low that the inter-particle distances are far greater than both the wavelength and coherence length, the wavefront must still be slowed slightly - and this must occur in the vicinity of the individual particles, rather than the large spaces of pure vacuum between them. 

Here is a rough attempt at an illustration, showing the wavefront travelling from the left to right, with red and blue for positive and negative electrical polarity (in the vertical direction, or at right angles to the plane of the picture) of the wave:

Diargramatic representation of plasma redshift - dimple redshift 

Update 2006-09-11: I have calculated an impulse which has the same spectrum as blackbody light, and it is much shorter than the multiple up and down waves I have illustrated above.  Please see: ../simmering/#impulse.

As the wavefront is slowed by the particle (indicated by the dot, but with concentric circles to show what we might think of as contours of light-slowing influence for light of about this wavelength), it temporarily couples some of its momentum to the particle.  This can be shown via the following arguments / thought experiments:
A beam of light being absorbed, reflected or deflected transfers momentum to the object which absorbs it or changes its direction.  We know that such energy is deposited in quanta, each one resulting from what we later can describe as a "photon".  It is reasonable to assume that each such deposition carries with it a small quantity of inertia.  (A square metre of sunlight at the Earth - 1356 watts - conveys about 0.44 milligrams of momentum.  This is the mass of a drop of water 0.65mm in diameter.)

The wavefront contains the momentum - we can absorb electromagnetic radiation at all other places but wherever the wavefront is travelling, and the wavefront still exists and will couple its momentum when the "photon" collapses and delivers its energy.  For instance, as the wavefront of what we later observe as a single photon propagates through space, we can make the space in front of it and behind it opaque to light, without upsetting the wavefront itself. To the extent we can do this whilst not altering appreciably the probability of its energy and momentum being deposited as a "photon" in the same locations as it would if we had not made space opaque, then we can reasonably say that our moving band of transparency in an otherwise opaque space contained the wavefront as it travelled.

So the momentum must exist in the wavefront, even if the source no longer exists and the destination is not yet known or does not yet exist. 

A second thought experiment, considering how a prism bends light, shows that when the light enters a medium which slows it, that some of the momentum is physically coupled to the surface of the object where the slowing occurred.  Likewise, when the light emerges back to full vacuum light speed, it pushes back against the surface it emerges from by a similar amount, to restore its vacuum speed full momentum.  The proof is that the two surfaces of the prism deflect the light beam to a different path, and so give it some momentum at right angles to its initial trajectory, whilst also reducing its momentum in the initial direction.  All the action in this occurs at the surfaces of the prism, so its here that the momentum must be partially coupled to the glass.

A wavefront of light passing into a glass block couples some momentum to its front surface, according to how much its speed is slowed.  On re-emerging at the other side the same force is made against the rear surface as the photon regains is normal speed.  We would expect a temporary coupling of inertia from the wavefront to any object which slows it, including a thin piece of glass, which is thinner than the wavefront, or even a soapy water film.  Since we know that overall, any plasma slows the light (and therefore temporarily receives some of its inertia), we expect that the edge of a dense plasma will receive some fraction of the inertia, just as the front edge of a block of glass does.  When the plasma is so low in density that the interparticle spacing is greater than the wavefront thickness (AKA "coherence length"), each particle is like a separate, independent, obstacle to the wavefront, which would otherwise be travelling at full vacuum light-speed.  So we expect the wavefront to couple some momentum to the particle as it approaches it, and to kick back against the particle as it proceeds onwards, just as it would a small block of glass.

Because the deformation in the wavefront (due to it being slowed in the vicinity of the particle) is always behind the rest of the surrounding (full light-speed) wavefront, I believe this temporary coupling of momentum to the particle does two things:
  1. It drags the particle in the direction of the propagation of the wavefront.  This is a net conveyance of momentum - the particle never gives back its momentum fully to the wavefront, whereas if the wavefront travelled through a block of glass then on emerging, the block gives up all the fraction of momentum it absorbed when the wavefront entered it.  This is a gut-feeling aspect of the theory - highly qualitative and something I want to think about a lot more.  (For instance, if a solitary particle in space is bathed in photons coming from one direction, the particle is continually distorting the wavefront of the photons, which I think is doing work on something which contains momentum.  Therefore, I figure the particle must be tangling with the wavefronts and must, overall, gain some momentum in the direction of the travel of the light.  The asymmetrical deformation of the wavefront is what makes me think the particle is exerting forces on the wavefront which are not entirely returned.)

  2. The photon continues with less energy - a lower frequency and longer wavelength.  It is redshifted.
I can't at present describe this in a more technical manner. 

Such an effect would be hard to measure in the lab, because it is a very slight effect, and it can't generally be observed with coherent light, such as from a laser, since the coherence length (and therefore the thickness of the wavefront) is so long that we can't make a sufficiently sparse plasma for the inter-particle distances to be larger than the coherence length of the light.   Doing the test with short coherence length light is easy - but that is of many wavelengths, so would be hard (surely impossible in the lab) to measure the redshift.  Maybe using a solar furnace and an artificially created low-density plasma of a density such as that found in the transition region or low solar corona, it would be possible to measure some energy absorption in the test plasma by chopping the light on and off at tens to thousands of Hertz - and by measuring energy and/or momentum deposition in the plasma which is in phase with the chopped light.  See the section below on experiments: #experiments .

For a given wavelength of light, with a given coherence length, the relationship between plasma density and redshift follows the pattern shown below.  At zero density there is zero redshift.  As the density (number of particles per cubic volume, which is proportional to the number of particles encountered by a "photon" per unit distance) increases, redshift rises linearly - until a limit is approached, after which the trend is to less increases in redshift, and then to less redshift and ultimately (at high enough densities) effectively no redshift whatsoever.

That limit is where the increased plasma density means the decreased the inter-particle spacing leads to the wavefront, on average, engaging with two ore more particles inside whatever volume of space (say roughly a sphere with diameter equal to the coherence length, or perhaps a three-dimensional ellipse, as long as the coherence length and about 1 or 2 wavelengths in diameter) which results in a generally continuous slowing of the wavefront.  In other words, as the density approaches that required to provide an homogenous medium which slows the wavefront evenly rather than just close to each particle, the redshift declines towards zero.

Sorry about the lousy graph. I am yet to figure out how the redshift changes with wavelength. For instance, do X-rays generally have less redshift than visible light, because these "photons" seem to pass between most matter, even in solid objects? What of the CMB? 

Perhaps if protons are greatly more effective at slowing light compared to electrons, then the plasma-redshift process would be relatively insensitive to the locations of the electrons.  All that would matter is the wavefront encountering protons far enough away from other protons that it is like, to a significant extent, the wavefront enountering the proton on its own in vacuum. 

The process could be more complex than I have imagined.  Maybe it only happens when a proton (or other nuclei or ion) is close to an electron, but not close to any other protons.  Perhaps the electron is needed for whatever mechanism by which the wavefront delivers a little of its energy.  That would make sense, since without another object to push against, the wavefront can't give one particle any kinetic energy, except by delivering momentum - yet that momentum is the mass-energy of the energy it delivers.

If that is the case, then perhaps the process is an operation on an electron which is near a proton, but not as near or in orbit as an electron would be in an atom.  This sounds reminiscent of Paul Marmet's theory about hydrogen atoms - just with the electrons further away, but still close enough that the wavefront can do something simultaneously to both particles.  Maybe then it is a special case of free-free absorption, operating on a pair of particles, as free-free absorption does, but without the quanta being absorbed or scattered - just with it being redshifted a little.  Maybe there's some wacky quantum mechanical effect which only manifests with two particles close to each other.  However, any such two-particle theory seems predict that the strength of the effect would be proportional to density squared, since it can only happen when two particles are within some distance of each other.  For instance, halving the number of protons and electrons in a cubic metre means that there is only 1/4 of them on average spending time within a certain distance of another particle.  This would make the effect vastly less effective in low-density plasmas such as the solar wind or the Void IGM.

There are all sorts of implications of this redshift mechanism.  For instance it would affect different wavelengths to different degrees for a given plasma, since such wavelengths would (typically) have different coherence lengths and so be more or less affected according to how this compared with the distribution of particle spacings.   An initial, perhaps naive approach to this is as follows:

Emission lines would be less redshifted than continuum light (black-body, synchrotron etc.) because they are the product of resonant systems, which produce photons of long coherence length.   The situation with absorption lines is trickier still - what would happen?  Would the surrounding continuum wavelengths be redshifted a lot and so shift the whole line to the red?  Or is the finely tuned absence of certain wavelengths itself a highly resonant, and therefore long coherence length, property of the light - making it only subject to redshift in a plasma with sufficiently large interparticle spacings?  If so, then wouldn't the surrounding continuum wavelengths be shifted into the wavelength of the absorption line and fill it up?   This is where we need to consider the entire system, potentially spanning the visible extent of the Universe, as a single quantum mechanical system.

Plasma redshift such as this could provide explanations for the cosmological redshift and the redshift of quasars - by one or more shells of plasma around the core which is sparse enough to redshift the light, but which is denser than the inter-cluster medium, or the Void IGM, and therefore provides more redshift per parsec than the Void IGM.  (More on this below in the section on the Transverse Proximity Effect.)  It could also explain the differences in redshifts between emission lines, which typically form near the core of the quasar, and absorption lines (formed by cooler gas further from the core) - an intervening layer of redshifting plasma makes the near-core emission lines become redshifted by the time they pass through the outer layer which does the absorption, with the distance between the two being very much less than that normally assumed based on the expanding Universe Doppler=distance theory.  See footnote on different redshifts of QSO emission and absorption lines.

The "Lyman forest" can be explained by multiple clouds of H I (atomic hydrogen) fairly close (AUs to light years?) to the quasar core, but separated by bands of redshifting plasma.  (Why there are such clouds containing neutral H, near a quasar and amongst all this plasma, is another question . . . ) If the jets of a quasar punch through such layers, then this would explain why we don't (usually) see Lyman forest absorption lines in the broad spectrum light of BL Lac objects.  (I assume that what we call a "BL Lac object" is us looking at a quasar straight down one of its jets - but maybe there could, in some cases, be clouds of redshifting plasma and/or Lyman absorbing neutral H I beyond the lobes of the jets, which would give rise to Lyman forest lines and other absorption lines at one or more parts of the increasingly redshifted light's travel.)  Likewise, Lyman forest lines could be explained by H I clouds well away from the quasar, in the midst of the IGM - with the IGM doing the redshifting between clouds.  But I suspect that most of these clouds and/or shells of absorbing H I and redshifting plasma are local to the quasar's general vicinity - products of collapsing material, being heated and perhaps at times driven away by radiative losses coupling momentum to them.   (Below I discuss how these Lyman Alpha forest clouds can be investigated with the Transverse Proximity Effect: #TPE .)

(This raises all sorts of interesting questions.  A quasar which is a black-hole driven by accretion may starve itself if it is only feeding on sparse IGM plasma / gas if the light it puts out is absorbed sufficiently to radiatively accelerate the IGM away from the quasar.  Then it would fade, and the accretion would begin again . . . but it only takes a star or dust cloud or the like to wander into the vicinity for there to be plenty of feedstock to power the quasar and keep up its heating and repulsion of redshifting plasma in a shell around it.  Furthermore, do black-holes eventually (to us - but fairly quickly, perhaps, according to the time experience of the infalling matter), split due to some process driven by the angular momentum they contain?  If so, then this could explain Halton Arp's theory that quasars are emitted by large black holes / quasars in disturbed galaxies.  The new-born quasars, or quasar pairs, would need to be initially surrounded by a substantial shell of redshifting plasma to explain his observation / hypothesis that they are, at first, high redshift and low luminosity.  Even if all this is true, I wish I could think of a model to explain Halton Arp's engaging thesis that certain types of galaxies pop out pairs of quasars, in opposite directions, with those quasars maturing, becoming lower redshift and higher luminosity, and then evolving into BL Lac objects and ultimately clusters of galaxies!  This is such a fabulous, distributed, feminine, story compared to the boy's own Big Bang - but I suspect that reality is not quite like this charming theory.)

Assuming that the coherence length (AKA wavefront thickness) is generally proportional to wavelength, this redshift theory predicts less redshift for microwaves than for visible light - except where the plasma, such as the Void IGM, is of a sufficiently low density that the interparticle spacing is greater than the microwave coherence lengths.  But perhaps, for shorter wavelengths, such as X-rays, the photons hardly ever encounter matter, so they are not redshifted very much at all.  One possible arrangement of my plasma redshift theory is that only when a photon's path (this is fictitious - just one way of looking at the situation) comes within a wavelength or so of a particle, it is subject to redshift.  Since X-rays are such short wavelengths, they tend to pass through plasma for longer distances on average than a photon of visible light before coming close enough to a particle to be affected by it. 

I wonder about the redshift of 21cm and other emission lines of microwaves in the jets and lobes of radio galaxies, compared to the redshift of light from their optically visible core.  Showing that these two redshifts were identical would be serious challenge to, or disproof of, my plasma redshift theory, since I guess that even in the Void IGM, the interparticle distance is not so long as to be greater than the coherence length of the 21 cm waves - so I would expect these waves to be less redshifted than visible light.

Footnote on the different redshifts of QSO emission and absorption linesBack to the reference.

If it can be shown, as apparently it can, that QSOs often have absorption lines with different redshifts from the emission lines, then this should be a clear sign that a non-Doppler redshift process is at work.  The emission lines are thought to come from the core, or near the core (high temperature ionized gas heated by other photons arising from the core's accretion disc synchrotron radiation) and these are typically found to be redshifted with respect to the absorption lines.  The nature of the absorption lines shows that they arise in cooler clouds of gas, presumably some distance from the core.  While some absorption lines are seen to be red-shifted with respect to the emission lines, or at the centre, or close to, the emission line of the same species of ion, I understand that the emission lines are typically found to be redshifted with respect to the absorption lines. 

Another typical, almost universal, feature is that the absorption lines are narrow and the emission lines are broad. 

If the only source of redshift is Doppler caused by the expansion of the Universe, then the blueshift of the absorption lines with respect to the emission lines implies vast distances between them, which are improbable, since presumably the gas clouds which cause the absorption lines are structurally centred on the quasar's core, due to the fact that they are found in most quasars.  This would imply a thin spherical shell of absorbing gas, surrounding the quasar, but expanding with the expansion of the Universe.

Alternatively, if the absorbing shell is considered to be expanding due to outgoing velocity from the quasar, in addition to whatever velocity would be due to the expansion of the Universe, then there is the problem of how the quasar could continue to feed on matter, since the expanding shell would presumably not exist if matter was falling through it. (However, it could be argued that stars and galaxies do fall through the shell . . . or that the quasar continues to feed on its "host galaxy".)

The breadth of the emission lines is generally explicable by turbulence and especially circular motion of an accretion disc (depending on what angle we view it from).  The narrowness of the absorption lines means that the cloud of gas which gives rise to them must be moving uniformly, as a unit, at a constant velocity with respect to Earth. That is, it cannot be expanding or collapsing along the line-of-sight.  Typical conventional explanations for this is that the quasar is ejecting a shell or isolated cloud of cooler gas at some substantial fraction of the speed of light.  But how could this be explained in the face of the following two objections?  Firstly, hurling something at that speed is unlikely to result in it remaining cool.  Secondly, a typical violent process which flings a cloud of gas in a general direction will result in different parts of the cloud having different velocities - but we typically do not see this at all, because the absorption lines are very narrow.  A further objection is that such ejections of substantial quantities of matter, especially a complete shell of gas surrounding the object, seems to be contrary to the pattern we expect of a black-hole.  How could they keep up a trajectory through the surrounding IGM?

A much more satisfying explanation is that the shell of absorbing gas is not moving at any great speed with respect to the core of the quasar (which is presumably the centre of the accretion disk which is, or is close to, the material giving rise to the emission lines) - and that the redshift of light before it passes through the absorbing cloud is caused by plasma redshift in the distance (light weeks, months and years, perhaps) between the core and the absorbing cloud.

Some references are:

Coronal heating and solar wind acceleration

This redshift theory would also explain the statistically excessive redshift observed in the spectra of hot stars - which I would expect to have a more extensive corona, and so subject their photospheric light to more redshifting plasma.   Halton Arp wrote about these observations about hot stars (after being rejected on the basis that conventional theory should have proved his observations wrong . . . see page 101 in "Seeing Red") in Monthly Notices of the Royal Astronomical Society 258, 800 and Ap. J. 375, 569.  1992MNRAS.258..800A  1991ApJ...375..569A  I am keen to follow this paper's references and find independent evidence of this purported effect. 

In my rough, entirely qualitative (so far) Dimple Redshift theory, I predict that a wavefront of what we later describe as a "photon" encountering a lone particle (such as an electron or proton) suffers redshift (and therefore energy and momentum loss) in proportion to the mass of the particle multiplied by its charge.  This relation probably only holds approximately linearly within certain limits.  This is based on my very rough understanding of the correlation between a substance's refractive index (propensity to slow light) and the mass of its constituent atoms. 
However, I found at:  that the refractive index of hydrogen molecular gas (1.0001392) and deuterium molecular gas (1.000138) are little different, and that the heavier one has a slightly lower refractive index.  I recognise that the refractive index of a substance varies according to wavelength, as well as temperature, pressure and density.  I am keen to understand a way of estimating the refractive indices of low-density plasmas, from a first-principles understanding of their constituent particles.  For instance, does a very low density deuterium plasma have a higher refractive index than a similar plasma made of ordinary hydrogen.  (By the way, I was intrigued to find from the abovementioned page that the refractive index of liquid helium is only 1.024, which would make it very hard to see.)

If this is the case, the momentum coupled to electrons, protons and ions (including heavier bare nuclei and nuclei which still have one or more electrons) is proportional to the particle's charge multiplied by its mass. 

That being the case, the velocity gained by the particle, for a photon of given energy, is proportional to its charge.  (I anticipate that the loss of energy by the photon is somehow translated into random - "thermal" - velocities, though I am not sure how this is achieved, except by pushing against other particles, in order to conserve momentum.  I anticipate that the lost energy from the photon manifests as a transfer of momentum from the photon to the particle, in the direction of the travel of the photon - so accelerating the particle away from the Sun.  However, when close to the Sun, with the photons coming from a variety of angles from the nearby solar disk, this would also manifest partly as random "thermal" velocity changes.)  This would explain the observation, as I understand it (see 2.1 and 5.2 in the Stephen Cranmer review paper referred to below) that the heavier nuclei are the fastest moving species in the extended solar wind.  This has no conventional explanation, as far as I know.  With Dimple Redshift, this would arise from many redshift encounters leaving the particle with substantial momentum away from the Sun, and the reason these ions and nuclei are accelerated to the highest velocity is not because they are heavier, but because (when stripped of most or all of their electrons) they have the highest charge.  (Perhaps this could be verified with solar wind detectors, which routinely pick up many of the element's in various degrees of ionization.)

Various magnetic wave processes have been proposed for the preferential heating and acceleration of heavier ions in the corona and extended solar wind.  Perhaps plasma redshift deposition of energy and momentum would play a significant or dominant role in this acceleration and heating.

On page 233 of Steven Cranmer's paper there are diagrams showing the temperatures of three types of ion - helium, oxygen and neon - as ratios of the local proton temperature, at 1AU (Earth's distance from the Sun) for various wind speeds.  The high-speed wind is believed to be the ambient condition - that resulting from coronal holes (polar and equatorial, which may lead to differing wind characteristics)- and the lower speeds are believed to result from magnetically active regions of the photosphere and low corona.  Temperature ratios at the higher speeds are about 6 (helium), 20 (oxygen) and 70 (neon).  Perhaps my plasma redshift theory (such as it is) can contribute to an explanation to these great variations in temperature with respect to the protons in the same solar wind.

Here are some quotes from page 255 (I also quote this text later in this page, sorry about the repetition).  Quotes are in dark green and inverted commas, but I have added some text in black and [square brackets] to try to replicate the meaning of symbols which can't easily be replicated on a webpage.  Unfortunately Microsoft Internet Explorer, for me at least, does not recognise the tilde character - the horizontal wiggly line - " ~ ", so I have a .gif file to do this.  So > this means "tilde greater than" by which I mean "greater-than or about equal to".

"In the 1970s and 1980s it became clear that even the most sophisticated solar wind models could not produce a fast wind (u > 600 km s?1) without the direct addition of heat or momentum in some form (e.g., Holzer and Leer 1980). Further, it was found that energy needs to be deposited both close to the solar surface (to produce the sharp transition region) and at a large range of distances in the extended corona into interplanetary space (to accelerate high-speed streams, to prevent pitch-angle beaming to T [temperature of random velocities parallel to line of travel from Sun] >> [is much greater than]  T? [temperature of random velocities at right angles to line of travel], and to account for observed superadiabatic temperature gradients). The physical processes responsible for this energy deposition have not yet been identified with certainty."
. . .

"Both the plasma density and the volumetric heating rates decrease rapidly with distance from the photosphere, but the heating rates per particle are of the same order both at the base and in the wind acceleration region."

However the various magnetic wave theories seem to operate only at particular distances, and fail to account for the acute onset of heating in the transition region. (This is conventionally explained as resulting from discontinuities in the relationship between plasma temperature and its ability to radiate energy, by there being a plateau of temperature in the upper chromosphere until hydrogen is fully ionized and in terms of the corona's EUV - Extreme Ultra Violet - radiating downwards.  These seem reasonable, but I suspect that they are only a part of the explanation.)  The relatively constant heating rate per particle ("the same order" in the context of very large variations in density) is well explained by a plasma redshift process such as mine because the particle (electron, proton, helium ion etc.) is subject to a relatively constant illumination.

The acute heating in the transition region seems to occur all over the Sun, irrespective of local magnetic conditions (other than strong fields in active regions causing disturbances and concentrations of plasma and/or heating activity).  The sharp onset of heating in the transition region seems to occur on such a small spatial scale that most or all of the magnetic wave theories cannot account for it.  Most magnetic wave theories involve slow waves, such as approximately 0.01 Hz, radiating from the photosphere, but the heating at the transition region seems to be relatively constant, despite evidence of some material travelling downwards at great rates, and of other explosive and oscillatory (300 seconds) events.

Consequently, there are suggestions that the transition region is heated by downwards EUV (Extended Ultra Violet) radiation from the higher corona, which is supposedly magnetically heated.

Here is a slightly graphically enhanced graph of temperature and density in the transition region, from: with my annotations to show the approximate inter-particle distances at the various densities. 

Temperatures & densities in chromosphere to corona, annoted to show inter-particle spacing

The three yellow pointed objects are representative of the scale of the spicules which erupt from time to time, in accordance with the vertical dimension of the chart being elevation above the photosphere.  The purple line is the temperature, rising to over 1,000,000K as per the scale at the bottom.  The dotted line is the density, in grams per cubic cm, as per the scale at the top.   The photosphere density is just less than 10-6 grams / cm3, which is 1/000 of the atmospheric pressure on the surface of Earth.  The lines at the top refer to different ways of creating vacuum on Earth, as explained in the caption.  Likewise, the numbered vertical lines on the lower left refer to man-made temperatures, with 4 being an oxy-acetylene flame and 5 being an electric arc.

On an average computer monitor, this is a scale of about 100 km per mm.  The Sun''s diameter is 1,392,000 km - that would be 13.9 metres on this scale

NASA's caption is:
"TEMPERATURE AND DENSITY vary with height in the Sun's atmosphere according to these curves. Height in kilometers is shown increasing upward on the scale at left, measured from the top of the photosphere where sunspots are seen. Yellow and orange peaks are chromospheric spicules that jut up into the corona; the transition region between chromosphere and corona is shown as a dark yellow band, only a few hundred kilometers thick, which follows the spicule outlines.

At the top of the photosphere (zero height) the solar temperature is about 6000 K; below this, in unseen layers of the solar interior, the temperature increases as the center of the Sun is approached. Temperature continues to fall above the photosphere until a sharp minimum occurs in the low chromosphere. The temperature of the solar atmosphere then begins to rise, slowly in the upper chromosphere, and then rapidly, in steps, through the thin transition region. At a height of about 5000 km above the photosphere, in the corona, a temperature of 106 K and more is reached. Numbered temperature lines at lower left show familiar laboratory temperatures such as (1) temperature at which gold melts, 1337 K; (2) melting point of iron, 1808 K; (3) boiling point of silver, 2485 K; (4) temperature of acetylene welding flame; and (5) iron welding arc. Higher temperatures to right of (5), which characterize most of the solar atmosphere, are seldom achieved in our terrestrial experience. Density of the gaseous solar atmosphere falls rapidly with height above the photosphere. (See the scale at top, expressed in grams per cubic centimeter.) Between the photosphere and the top of the transition region, in a range of less than 3000 km in height, density falls through 10 orders of magnitude. Even in the relatively dense photosphere, the solar gas is so thin that it would be considered a vacuum on Earth. Lettered lines at top give terrestrial densities such as (A) density of our atmosphere at an altitude of 50 km, (B) Earth atmosphere at 90 km; (C, D, E) ranges of vacuum densities achieved by laboratory vacuum pumps: (C) mechanical vacuum pump, (D) diffusion pump, and (E) ion pump. "

Note how the transition region is at the top of the chromosphere, including when the chromosphere rises as spicules.  This is still the way these parts of the solar atmosphere are generally understood - the transition region exists in much the same way as usual, on the sides of the spicules.

I have added indicators about the average inter-nucleus distance - on the following relatively crude basis.  Firstly, I have counted hydrogen and helium nuclei as the same, while helium makes up about 10% of the atoms of the photosphere, which is about 28% of its mass.  Secondly I ignore the heavier elements which make up about 2% of the mass - with each one having an abundance of no more than 1/1000th of hydrogen.  I count a nucleus either in the form of neutral hydrogen or helium atoms, or as protons or alpha particles in a plasma with electrons.  In a hydrogen plasma, there would be the same number of electrons as well.  But in a fully ionized plasma made of photospheric material (actually the concentration of helium changes at higher altitudes depending on what part of the Sun this is), there would be more electrons than protons, because for every proton there are about 9 helium nuclei, each of which contributes 2 electrons - and similarly more electrons still per nucleus of the heavier elements.  So when the material is ionized the number of particles approximately doubles because for every 90 hydrogen atoms and 10 helium atoms 110 electrons are also freely moving in the plasma.  Thus, the particle density of such a plasma is about 2.1 times its density as neutral atoms.  This leads the inter-particle spacing dropping to (1 / 2.1-3) =  0.78 of the value found in the same mass density of neutral atoms.

This "inter-nucleus" measure is not intended to be particularly accurate - just to give an idea of the state of the neutral gas or plasma at the various densities, which were originally labelled as grams per cubic cm.  I convert grams of gas or plasma into numbers of nuclei by assuming an average nucleus has a mass of (0.9 x 1) + (0.1 x 4) = 1.3 hydrogen atoms .

0.1 micron spacing
= 103 nuclei per cubic micron
= 1015 nuclei per cubic cm
which have a mass of 1.3 x 1.67 x 10-9 = 2.17 x 10-9 grams
2007-01-23: I replaced this text with something new.  (I fluffed the grams per cm3 increments!)

2.17 x 10-8 grams per cm3 would have an inter-nucleus spacing the cube root of 10 (2.15) times 0.1 = .215 micron.

2.17 x 10-7 grams per cm3 would have an inter-nucleus spacing the cube root of 100 (4.64) times 0.1 = .464 micron.

2.17 x 10-6 grams per cm3 would have an inter-nucleus spacing 10 times 0.1 = 1 micron.

As is discussed below, the approximate coherence length of photospheric light - white light, centred on about 0.5 microns (0.5 um) - is probably between 2 and 8 microns.  Between the photosphere and the corona, the density drops by a factor of about 1011  - corresponding to a range of about 1 : 5,000 in inter-particle spacing.  According to my rough theory of plasma redshift, the effect should begin to operate in earnest once the inter-particle spacing is 1 to 3 times the coherence length.  In this 1 : 5,000 range of inter-particle spacings, it can be seen that the rate of temperature rise undergoes the most rapid increase at about the density this theory predicts.  While I don't yet have a precise formulation of the relationship between inter-particle spacing and redshift, in this 1 : 5000 range (103.6), we observe a very rapid heating within a factor of two or three of the predicted interparticle spacing (100.5).

2.17 x 10-10 grams per cm3 would have an inter-nucleus spacing the cube root of 10 (2.15) times 0.1 = .215 micron.

2.17 x 10-11 grams per cm3 would have an inter-nucleus spacing the cube root of 100 (4.64) times 0.1 = .464 micron.

2.17 x 10-12 grams per cm3 would have an inter-nucleus spacing 10 times 0.1 = 1 micron.

2.17 x 10-13 grams per cm3 would have an inter-nucleus spacing 10 times 0.215 = 2.15 micron.

2.17 x 10-14 grams per cm3 would have an inter-nucleus spacing 10 times 0.464 = 4.64 micron.

2.17 x 10-15 grams per cm3 would have an inter-nucleus spacing 10 times 1.0 = 10 micron.

These figures now accord approximately with my black annotations of the NASA figure above, which overstate the inter-particle spacing by 1/0.78.

As is discussed below, the approximate coherence length of photospheric light - white light, centred on about 0.5 microns (0.5 um) - is probably between 2 and 8 microns. 

Actually, it may be less than that.  See my work in late 2006: ../simmering/#impulse An impulse with most of its energy in 0.624 um has the same spectrum as the black-body spectrum of sunlight, so we can imagine a wavefront which is only about 0.7 microns long speeding up nicely to light speed and then slowing down for a particle, when the average inter-particle spacing is about 2 or more microns.  There is a huge change in density within the Transition Region, spanning this particular density: 2 x 10-13 grams per cm3 .  According to the NASA diagram, the density range spans about 10-13 to 10-16 grams per cm3. 

Thus, at the bottom of the Transition Region, the average inter-particle spacing is probably about 1.3 microns, and at the top, about 13 microns.

The Transition Region is where the material really "catches fire".  It spans 3 decades of density change (by mass per unit volume) - and my hypothesis (and I guess Ari Brynjolfsson's) predicts that within this density range, the plasma redshift process should begin to function strongly.

Thus, my hypothesis predict the onset of heating within the same 3 decade range, out of the full 11 decade photosphere to corona range as where the heating is observed to begin in earnest. 

End of modifications on 2007-01-23.

This chart is from NASA's Skylab historical section, a reproduction of a printed book:
Other URLs for this site are:
To get some sense of scale here, from: :

"OUR TINY PLANET EARTH serves as a yardstick to scale the thickness of the layers of the solar atmosphere. The photosphere (orange layer), where sunspots are formed, is about as thick as Alabama is wide - about 400 km. The less dense and more turbulent chromosphere (red-orange) spans several thousand kilometers, stretching on our scale from Alabama to Los Angeles. The intensely active transition region (yellow), first observed in detail by Skylab, is very thin-equal in width to metropolitan Los Angeles. Spicules (red) extend the chromosphere into the corona as pointed waves whose heights are roughly equal to Earth's diameter. Prominences (not shown) and the corona (black) reach far into interplanetary space, and are much too large for our terrestrial scale."

Each square metre of the Earth receives about 1,400 watts of energy from the sun.   This is equivalent to the output of about a 4.4mm square of the Sun's photosphere.  The energy radiated by each metre of photosphere is about 63 Megawatts.   The Sun is about 1.4 times as dense as water, 110 times the diameter, and has surface gravity about 28 times that of Earth.

Why does the gas leaving the sun get so hot?  Why does it keep getting marginally hotter as it leaves the Sun and as the pressure decreases?  Normally, pressure decrease leads to lower temperatures.

In particular, why, within a few hundred kilometers at the edge of a massive gas body with a radius of 695,800 km, does the gas suddenly rise in temperature about a factor of 100???
The heating is observed to begin in earnest once the inter-particle distance increases to a distance in the 3 to 9 micron range.  Heating at higher densities (lower inter-particle distances, below the transition region) is relatively mild and may be explained by absorption of EUV which is radiated downwards from the transition region and low corona.  (See below #Energy for more discussion of heating rates per particle.)

Probably the most detailed modelling of physical conditions in the corona and transition region, in order to replicate observations, without attempting to explain the heating / acceleration process by any one theory, is the set of three papers, the last of which is Vernazza et al. (1981):
Structure of the solar chromosphere. III - Models of the EUV brightness components of the quiet-sun.  Vernazza, J. E.; Avrett, E. H.; Loeser, R.  Astrophysical Journal Supplement Series, vol. 45, Apr. 1981, p. 635-725.

However, the work of this team in this and other papers is criticised for ignoring certain observations, by Harold Zirin (who wrote The Astrophysics of the Sun in 1988: ):
The Mystery of the Chromosphere 
Zirin, Harold.  Solar Physics, v. 169, Issue 2, p. 313-326
We discuss many aspects of the solar chromosphere from an observational point of view, and show that most existing models are in direct contradiction to radio and eclipse measurements.  We plead for attention to the actual observed radio temperatures and density gradients, as well as images of the chromosphere.  We find that the chromosphere is not in hydrostatic equilibrium and suggest that the support is due to the tangled intranetwork fields.

A large reference work on the solar transition region is "The Solar Transition Region", John T. Mariska, Cambridge University Press, 1992.  (See #Resources )

(Regarding a "To-do:" which was here, please refer to the "Dramatic events in the transition region" section below about acceleration of 1000 G and more.  It turns out this was due to figures which I now consider unrealistic.)

Another recent review of coronal heating theories is S. Oughton, P. Dmitruk, and W.H. Matthaeus. Coronal heating and reduced MHD. In Turbulence and Magnetic Fields in Astrophysics, E. Falgarone and T. Passot (eds), Vol. 614 (LNP) p. 28-55. Springer (2003). This can be found at Sean Oughton's site: - .  In this view, there is no question about the source of the energy which heats the corona - it is "(convectively) turbulent photospheric and subphotospheric motions".  These are believed to drive magnetic waves (but I am not sure how well observed these waves are - though we can't directly observe things much closer than 1AU).  The unsolved question is how these waves couple to the plasma in order to heat and accelerate it, with most of the action taking place within a "few solar radii".

Some papers on the higher velocities and/or temperatures of heavy ions in the solar corona and solar wind:

Differential flow between solar wind protons and alpha particles: First WIND observations
Steinberg, J. T., A. J. Lazarus, K. W. Ogilvie, R. Lepping, and J. Byrnes, Differential flow between solar wind protons and alpha particles: First WIND observations, Geophys. Res. Lett., 23, 1183-1186, 1996.
Observations at 1AU in the ecliptic - that is, in the Earth's orbit.  Table 1, line 5, alpha particles (helium nuclei) are travelling at 18+/-20 km/sec faster than protons in the high-speed (>500 km/sec) solar wind.  Refers to papers which show that the alpha particle temperature ranges from 1 to 10 times that of protons.  Likewise alpha particle / proton ratios vary between 0.35 and < 0.01.


Steven Cranmer
has many papers: .  See his excellent review paper:
Coronal Holes and the High Speed Wind
Steven Cranmer
Space Science Reviews 101: 229?294, 2002:

Also (added 2009-02-05) another critique of the magnetic wave coronal heating theories, pages 128 and 129:
Physics of the Sun?s Hot Atmosphere
B. N. Dwivedi  J. Astrophys. Astr. (2006) 27, 125?137


Here are some comments on Steven Cranmer's paper, and quotes in dark green and inverted commas, with my boldface and highlighting. 

Page 238, Figure 3:
The top section shows oxygen ions having a much higher temperature than protons or electrons, by a factor of more than ten.  This remains the case as the wind travels out past 1AU to a distance of 400 solar radii (278 million km) at the right edge of the graph.  Assuming 850 km sec-1, this takes 90 hours.

Page 240:
Heavy ions travel faster than protons at distances of 0.3 to 1.0 AU.  The speed differential is approximately that of the "Alfven" wave speed.  (I don't have a clear understanding of these waves, but they are apparently purely magnetic waves, travelling along the lines of magnetic field lines, without associated gas/plasma compression, which makes no sense to me.)  (To-Do: what exactly are these higher velocities?)  Maybe plasma redshift can explain both the higher temperature of the heavy ions and their faster outward velocities, though both tend to return towards that of the protons (far more numerous and collectively more massive) over time, as the wind moves away from the brightest sunlight.

Page 242:
Polar plumes in polar coronal holes still require the plasma be heated, just like the ordinary coronal material in polar coronal holes.

Page 244:
"Thus the bulk of the solar wind acceleration must occur above 3 solar radii [2.5 solar radii above the photosphere] for the equatorial coronal hole."
How can magnetic waves carry (or connect back to the sun, to push against it) momentum out this far, except perhaps as a rotating centrifugal/centripetal function of the mass of rotating plasma?  Plasma redshift is a mechanism which could heat and accelerate charged particles at any distance, in proportion to the intensity of the sunlight.

Page 248:
It is not clear to me (Robin Whittle) from many of these coronal / wind heating / acceleration papers how well their various postulated magnetic waves are supported by observations.  The general theory is that the pulsations of the photosphere generate magnetic waves in various modes and that one or more of these dissipate energy in the transition region and/or corona.  Also, there is a DC current heating theory, which I don't clearly understand, and which seems (to me) to involve currents flowing through the corona, but always to and from different parts of the photosphere.  

Here is a critique of the discrepancy between the postulated magnetic waves, which must have small wavelengths to have any hope of dissipating in any of the postulated mechanisms in the corona, and the observations which should show evidence of such waves if they existed:
"Mancuso and Spangler (1999) found that the correlation length, or typical scale of the waves causing the Faraday rotation fluctuations, is at the very least 0.15 solar radii (i.e., 105 km), and is probably larger by a factor of up to an order of magnitude. There is thus a vast mismatch between the scale at which there is observational evidence for magnetic field fluctuations, and the scale which would permit efficient dissipative coupling to the kinetic energy of ions."
The discussion which follows this indicates that the observations were not a complete disproof of the existence of the postulated waves, but that ordinarily, such waves would probably have lead to differing observations.

Page 250:
This concerns theories of how the solar wind may "boil off" the corona - and therefore not require any further energy deposition.  Initial theories of a single fluid (all electrons, protons and ions having the same bulk and thermal motions) failed to predict the observations. 
"However, conductivity and collisions were not strong enough to combat adiabatic cooling for protons at large distances (Tp ? r?4/3) and the resulting proton temperatures at 1 AU were too small by orders of magnitude. Holzer and Axford (1970) found that a perfectly adiabatic corona (with polytropic index ? = 5/3) cannot even produce a time-steady supersonic solar wind. The conclusion at this time was that some as-yet-unknown energy source was required to heat the corona and maintain a high gas pressure beyond the point where conduction and collisions are important."
New theories involved "two fluids" - separate populations of particles, which were generally not colliding with each other. (Note, a small proportion of the solar wind electrons and protons / ions do recombine to form neutral atoms.  See .)

Page 253:
One theory of acceleration of heavy ions is an electrical field caused by electrons being swept ahead of them, for instance due to the higher thermal velocities of electrons (with the same thermal energies as protons) in the corona making it possible for them to escape the Sun's gravity.  This is called a Pannekoek - Rosseland electric field.  But I understand this theory is not in favour at present.

Page 255:
Coronal heating and acceleration mechanisms - we still don't understand what is happening.
"In the 1970s and 1980s it became clear that even the most sophisticated solar wind models could not produce a fast wind (u > 600 km s?1) without the direct addition of heat or momentum in some form (e.g., Holzer and Leer 1980). Further, it was found that energy needs to be deposited both close to the solar surface (to produce the sharp transition region) and at a large range of distances in the extended corona into interplanetary space (to accelerate high-speed streams, to prevent pitch-angle beaming to T parallel >> T perpendicular?, and to account for observed superadiabatic temperature gradients). The physical processes responsible for this energy deposition have not yet been identified with certainty."
The two very different areas of the coronal base (1 to 1.5 solar radii) and extended coronal areas beyond this are described, implying the need for different magnetically driven heating / acceleration mechanisms in each.
"Both the plasma density and the volumetric heating rates decrease rapidly with distance from the photosphere, but the heating rates per particle are of the same order both at the base and in the wind acceleration region. This implies that both regions are of comparable importance in influencing coronal particle velocity distributions, but because of their drastically different properties, it seems appropriate to consider these environments separately unless convincing evidence for a unified theoretical explanation arises."
Plasma redshift may be such a unified explanation, because it can deliver both energy and momentum to each particle according to the intensity of the light, assuming the interparticle distance is great enough for the effect to work.  This is irrespective of the magnetic fields, collision probabilities etc. which do widely differ between the transition region, through the corona and out to the extreme limits reached by the solar wind.

Page 256 - 257:
Heating in the chromosphere - transition region area is estimated to be about 5 x 105 erg per square cm (I think this means a 1cm square column of gas or plasma several thousand km thick) per second.  This is 1/20 watt - and it has been impossible to show how this can be achieved with magnetic wave dissipating energy in a plasma which is so thin as to rate as a pretty good vacuum on Earth.   But there is 6.34 killowatts of sunlight for each 1 cm square patch of the photosphere.   (If plasma redshift achieved this amount of heating, it would result in about 8 x 10-6 redshift, which is more than is observed in absorption or emission lines, but perhaps this amount of heating is a total amount, including active and concentrated coronal events, which are not where one usually looks for part-per-million redshifts of photospheric absorption lines.)
"The majority of this energy is deposited over a relatively small range of heights 0.01 to 0.1 solar radii [7,000 to 70,000 km] resulting in a local energy gain per proton of 0.01 to 1 eV s-1."

"Although many different mechanisms for base coronal heating have been proposed, the following general scenario is common to almost all of them.
(1) The churning of the Sun?s convective motions transports energy into photospheric magnetic flux tubes.

(2) This stored energy becomes organized into small-scale structures, probably with a complex topology and stochastic dynamics.

(3) Steep gradients at small scales are efficiently smeared out by Coulomb collisions or waveparticle interactions.

(4) The dissipated (kinetic or magnetic) energy becomes randomized, resulting in net particle heating. Traditionally, the suggested physical processes have been divided into two broad groups: AC (wave dissipation) and DC (current-driven reconnection)."

Page 259:
"It is now generally believed that the high-speed solar wind cannot be produced without the existence of gradual energy deposition above the base of the corona. Indeed, as spacecraft continue to probe the outermost frontiers of the heliosphere (> 50 AU), the measured solar wind temperatures remain significantly higher than expected from pure adiabatic expansion. In the extended corona, the proton heating rate per particle (i.e., Q/n) has been constrained to be approximately 0.1 eV s-1 at 2 solar radii (this is equivalent to a heating rate per unit mass, Q/?, of order 1011 cm2 s-3; see below), which is also of the same order as the heating rate per particle at the coronal base."
Providing 0.1 electron volt per second per particle (per "proton or electron" or "per proton and electron"?) seems non-trivial.  But these particles are bathed in intense sunlight . . .  I discuss these heating rates below: #Energy .

Page 267 - 269:

"The bottom line of this section is that the source of proton heating in the extended corona (i.e., 2 to 10 solar radii) is still not known. The situation is slightly better in the in situ interplanetary medium because the fluctuation spectrum can be measured directly (e.g., Leamon et al. 1998, 1999; Stawicki et al. 2001), but even there no self-consistent theoretical picture exists. The large number of possible mechanisms must be winnowed further by more detailed measurements of the plasma properties and fluctuations."
Perhaps we need a new theory, rather than more observations - even if its a theory which challenges or disproves the Big Bang theory.  With plasma redshift, energy lost from the passing light carries momentum, which may be sufficient to explain the motions of the extended solar wind.

Before proton temperatures in excess of 2 106 to 3 106 K in the corona were measured, the problem of accelerating the high-speed solar wind was considerably more vexing. The pressure gradient force on an electron conduction dominated plasma with a temperature less than or equal to 106 K could only produce an asymptotic flow speed of, at most, 300?400 km s-1. A source of extra momentum on the accelerating wind was justifiably sought, and such a force may still be a necessary component of a fully self-consistent model of the fast wind. Five of the most studied momentum deposition mechanisms are listed below.
Wave pressure
Resonant wave damping
Diamagnetic acceleration
Cosmic ray pressure
Gravity damping"

Page 271- 272:
" . . . flow speed differences of a factor of 2 to 3 may exist between adjacent Oxygen ions."


Heavy ions in the high-speed solar wind undergo preferential energization and a distortion of their velocity distributions away from Maxwellians. To lowest order, this energization manifests itself as:
(1) faster outflow compared to the bulk proton-electron plasma,

(2) more than mass-proportional heating, and

(3) temperature anisotropies that depart strongly from those of protons and electrons.
These  properties must be reproduced by any successful theoretical model. Even before a substantial database of ion plasma properties in the corona and solar wind had been accumulated, it was realized that ions cannot be in an idealized thermal equilibrium with the bulk plasma. Ions with temperatures of the same order as the proton and electron temperatures would receive a much smaller net outward acceleration than protons and electrons, as can be seen by estimating the contributions to ion acceleration from the pressure gradient, gravity, and zero-current electrostatic field . . . "
"It is now known (see 2) that ions are indeed more than mass-proportionally heated, both in the extended corona and in interplanetary space, and thus their rapid acceleration is not surprising."
But why are these heavier ions preferentially heated?  The paper discusses some possible mechanisms, such as concerning ion cyclotron waves and resonant zones in the corona, but these seem to conflict with proposals for high-frequency waves heating the extended corona.  Steven Cranmer gives his own critique of one such proposal.

Page 278, in conclusion:
"It seems likely, however, that different energy and momentum deposition processes are dominant in coronal structures with significantly different properties. Following Priest et al. (2000), we suggest the following qualitative hierarchy of structures (from high density to low density) that probably exhibit different dominant heating mechanisms:

1. active regions and bright points
2. quiet coronal loops
3. open funnels at the coronal base
4. open and closed flux tubes in streamers
5. open flux tubes in coronal hole acceleration regions
6. the high plasma ? interplanetary medium.
The plasma in coronal mass ejections (CMEs) obviously should also constitute a separate category, though its place in the above list is unclear."

R. G. Athay's published papers go back to 1953.  One paper from November 2000, which I can't find a full copy of on the Net, is:
Are Spicules Related to Coronal Heating? Athay, R. G. Solar Physics, v. 197, Issue 1, p. 31-42 (2000).
The abstract is:
We suggest that the waxing and waning of chromospheric and coronal heating leads to a dynamic solar atmosphere which, under the right circumstances, may produce spicules. Little is known about the heating process. However, Anderson and Athay (1989a) concluded from their study of chromospheric heating that the heating rate per gram of chromospheric matter is only a small fraction of the heating rate per gram of coronal matter. We postulate that the increased heating rate in the corona is a consequence of heating charged particles as opposed to heating neutral atoms. This leads to a specific degree of hydrogen ionization at which coronal heating begins to predominate over chromospheric heating. It also introduces the likelihood that the waxing and waning of the heating rates will have relatively large consequences in the levels where hydrogen ionization is becoming significant. It is demonstrated that changes in the heating rates are capable of inducing increases and decreases in coronal mass comparable to the mass contained in a typical spicule.
The highlighted text postulates that the heating mechanism is directly related to ionization.  This is not contrary to the various magnetic theories of heating, and is compatible with plasma redshift theories.  (R. G. Athay continues with this theme in "An Ionization Instability and the Base of the Corona" .)

However, Ari Brynjolfsson's theory, as I understand it, applies primarily to plasmas at elevated temperatures of 200,000 K or so, which are found only above the altitude at which hydrogen first becomes ionized. 


I have my own theories on spicules.  The following photo of rows of spicules is from: and seems to be from the Cambridge Encyclopedia of the Sun (see below):
solar spicules chromosphere transition region

It is widely accepted that their cores are are cooler chromosphere material, with the outer layer being the rapidly heated transition region. 

While they may well be associated with (caused in part by, and cause themselves) magnetic disturbances, I think they are primarily a body of cooler chromospheric material being kept cool, and swept upwards, by the pressure of the material above being rapidly "evaporated" once it heats up so rapidly in the transition region.  This is difficult to explain in text, and involves some counter-intuitive thinking, since the transition region is lower density than the cooler chromospheric material below it - but I suspect that the sudden heating of material as it enters the transition region causes it to expand suddenly, and in expanding into space above (with acceleration rates of 10,000 km s-2 or more), inertially pushing down against the upper chromosphere, partly or fully overcoming what would otherwise be a general lowering of pressure with increasing altitude.  Meanwhile, the higher pressure below this point (the lower boundary of the transition region) keeps the inter-particle distance low enough to avoid the onset of plasma redshift in the hydrogen ions (this is one view, see the section below on fractionation for another), which keeps it cool, until it expands sufficiently for the plasma redshift to occur in earnest.  (Also, perhaps expansion can't really take place until all the hydrogen atoms are ionized, because this is like melting ice: a lot of energy must be injected without raising the temperature appreciably, until all the ice is melted, or neutral hydrogen ionized.)

I believe that once the chromospheric material reaches a temperature which (at the ambient pressure in that location) expands it out to the inter-particle distances which enable plasma redshift to occur, that the heating occurs very rapidly, causing a rapid adiabatic expansion of the material as it is heated towards 1,000,000 K or so, and that this sudden (from the point of view of the slowly rising denser chromospheric material) heating causes such a rapid expansion, that the momentum of the plasma expanding away from the sun pushes down on the chromospheric layer below it, keeping it below the threshold of onset of plasma redshift.  (See the section below #TR-drama where it turns out that the expansion isn't as dramatic as I previously thought.) 

However not all the acceleration in the transition region might be attributed to adiabatic expansion - some of it may be due to the momentum of energy lost by sunlight in the redshift process and/or in some previously ignored absorption process.

In this view of "dramatic expansion", the transition region is like a detonation front, or a "flame front", above which the heated plasma blasts out into space due to its rapid expansion - and in so-doing, presses down against the material below it, keeping it dense enough to avoid plasma redshift, until that material is heated (by absorbing EUV from the plasma above, and also perhaps by diffusion downwards of high velocity particles) is itself heated and becomes the "flame front".   This description applies to the whole transition region. 

I believe the spicules, if viewed upside down (that is, the spicules point downwards) are analogous to vortexes in down-moving water between up-rising warmer currents when a saucepan of water is heated on a stove.   So the chromospheric material is pressed downwards (now we again think of spicules pointing upwards) between the spicules by the horizontal transition region all around, and the rapidly expanding corona above, and in certain places, like the gaps between rising columns of hot water in a saucepan, this pressure pushes chromospheric material upwards, where it is constrained by sideways pressure from the transition region material moving sideways on the edges of the spicules.  (Think of subduction zones, turned upside-down.)  Then, it is easy to imagine the material inside the spicule spinning, and the resulting centrifugal / centripetal forces and some associated (or driving, due to external forces from the photosphere) magnetic forces to create some kind of vortex, or string of such vortexes, relating to the photospheric network below.   Sorry this is a rushed description - I need more time and to do some diagrams!

There are many papers on spicules being caused by events below - magnetic fields arising in, or below, the photosphere and/or waves of pressure rising from the photosphere.  One such theory is by A. A. van Ballegooijen and P. Nisenson: "Dynamics of Magnetic Flux Elements in the Photosphere and the Formation of Spicules".  This is available as a PostScript file at:  (To convert this to a PDF, see below: #PostScript-PDF .) 


In mid April 2004, when I was preparing this page for its new home here at, I had not really looked at prominences.  When I read up about them, it became clear that plasma redshift provides a plausible explanation for why these immense volumes of colder, denser plasma remain so, despite being surrounded by million K coronal plasma, and indeed actively condensing the coronal plasma to add to the mass of the prominence.  Before discussing this, here are some references:

Aad van Ballegooijen has a number of papers at his site, as .ps PostScript files.  To view them with Adobe Acrobat, as .PDFs, follow the instructions below: #PostScript-PDF .  He wrote the  Solar Prominence Models in the Encyclopedia of Astronomy and Astrophysics ( #Encylopedia ) , and I recommend reading this in full:

Some pages on prominences:
The same object is known as a filament if we see it as an absorption of light from the disk, or as a prominence if we see it as a bright object against the sky, sticking out from the limb.

Natural light photograph of the chromosphere and prominences, taken during an eclipse by Jerry Lodriguss:
While most photos of prominences are taken with a filter to show the light at a very narrow range of wavelengths (typically caused by one species of ion, which is only present at a known range of temperatures) these show the chromosphere and a prominence as it really is, with the Moon kindly hiding the photosphere.  (There is also a beautiful, carefully composited, image of the solar corona at: .)

A prominence erupting into a plume:
This is still cool plasma compared to the corona around it, but I think it is expanding and being blown away from the Sun - by the pressure of the corona, and also probably by limited plasma redshift heating and momentum deposition as it becomes less dense.

Images and movies from SOHO .  Many of these are made using light from singly ionized Helium, which radiates at a specific short UV wavelength of 304 Angstrom (0.0304 microns) and only exists within a temperature range of about 60,000 to 80,000 K.  This temperature is normally found in the transition region / low corona, but it is also found in large active structures, and especially prominences, which are much cooler than the surrounding corona.  Maybe these images show a relatively thin border between the 10,000 K main body of the prominence and the 1,000,000 K or so surrounding coronal plasma.

Links in brackets contain a caption, other images, movies in other formats etc.
( )
Huge, detailed image of an erupting prominence on the lower left, with another prominence seen against the disk at the top left - the image I used on the home page of this site.

( )
Beautiful, informative, MPG movie (see the second link for Quicktime) showing large bodies of cool plasma suspended well into the corona, with some parts of this plasma following magnetic lines to other parts, or back towards the photosphere.  There is no ejection of prominences.
( )
Five images in one, taken in HE II 204 Angstrom (60,000 to 800 K), of an eruptive prominence blasting off over 5 hours.
( )
A very large prominence!
( )
Four large prominences, one rather twisted.

Some movies from This is a long page, with no targets.  I link to the MPG or animated GIF movie file, and copy some of the descriptive text so you can find it in the above page via searching.
EIT Fe XII 195 observation of an eruptive prominence/CME on the SW limb
A large eruptive prominence goes into emission . . .

We see what seems to be a relatively low prominence accelerate rapidly away from the Sun, to become, they say, a Coronal Mass Ejection.  This is the 195 Angstrom light from iron atoms which have had 11 electrons stripped from them.  This occurs at about 1.5 Mega K.
EIT Fe XII 195 observations of a general eruption of prominences on the NW limb
Pretty much everything ripped loose on 1998 January 3.

We see prominences rise and change then rapidly blast into space.
(Where are the SOHO movies used in the IMAX film Solarmax? They showed a number of prominences hanging like huge black thunderheads, comparatively static with the rest of the action, ominous, apart from fast streaks of material from the top of them to the sides.  That was fabulous, but the movie sucked in scientific terms - it didn't even mention how hot or big the Sun is, or how it is heated, or what scientists are still trying to figure out about it.  So manipulative and dumbed-down for the masses - as if ordinary folk aren't genuinely curious about the Sun, or capable of understanding some basic physics and appreciating the profound mysteries which remain.)

One promising paper does not seem to be freely available on the Net. (To-do: get it from a library.) 
Oscillations in Quiescent Solar Prominences: Observations and Theory - (Invited Review)
Oliver, Ramn; Ballester, Jos Luis
Solar Physics, v. 206, Issue 1, p. 45-67 (2002).
An extensive observational background about the existence of oscillations in quiescent solar prominences has been gathered during the last twenty years. From these observations, information about different oscillatory parameters such as period, wavelength, phase speed, damping time, etc., has been obtained. This observational background, combined with a growing number of theoretical studies about magneto-hydrodynamic waves in prominences, should allow the development of prominence seismology which, following helioseismology's approach, seeks to infer the internal structure and properties of solar prominences. The most recent observational and theoretical developments on prominence oscillations are reviewed here, with an emphasis on the aspects suitable to develop an observation versus theory feedback, but also pointing out key topics which should be the subject of future research for a further advancement of this field.

On dissipative effects in solar prominences
Ballai, I.
Astronomy and Astrophysics, v.410, p.L17-L19 (2003)
The Aad van Ballegooijen article Solar Prominence Models, linked to above, serves as the reference for this discussion.  He cites "MHD" (Magneto-Hydro Dynamics) as the heating mechanism for the corona, but I believe these models, as indicated by Steven Cranmer's review, are inadequate - and that plasma redshift is probably the primary heating mechanism.

The magnetic conditions for prominences seem to be pretty well established - and I won't repeat his description or diagrams here. Basically, relatively long-lasting arches of magnetic flux can develop at great heights in the corona, and if they have a "sagging middle" structure, they can behave like a trough and catch dense plasma, preventing it from falling back towards the photosphere.

The origin of the dense plasma in these areas is uncertain, but it seems clear that it is common for this dense, cool, concentration to act as a site of condensation - where hot (million K) very low density coronal plasma cools and adds to the mass of cooler, denser, prominence plasma.

The fate of the prominence may be to fall into the photosphere as the magnetic fields collapse, or for this cool plasma to follow magnetic lines sideways, or downwards.  Also, the lines of flux may expand outwards - and it seems this often leads to the cool prominence plasma being heated and both expanding enormously and being accelerated rapidly away from the Sun.  This "eruption of a prominence" is then (as best I understand it) commonly known as a Coronal Mass Ejection (CME), which is the largest type of event in the Sun's atmosphere, and is the greatest cause of solar wind disturbance of Earth's magnetosphere.

As best I can tell, researchers do not clearly understand what the general coronal heating mechanism is, or why it doesn't apply so strongly, or at all, to plasma in the prominences.

I found that my theory of plasma redshift (such as it is) and probably Ari Brynjolfsson's, provides seemingly useful explanations for the heating, and why this denser prominence plasma is not as hot as the usual coronal plasma.

My knowledge of prominences is limited and I am not trying to discuss or explain everything about them, such as what Aad van Ballegooijen describes as (p 5):
"Another complication is that prominences have filamentary structure, with thin (sometimes vertical) threads of dense plasma embedded in a much more tenuous medium.  This allows the ultraviolet radiation to penetrate deep into the prominence, greatly enhancing the excitation rate compared to models without such fine-scale structures (Heasley and Mihalas 1976).  The cause of these fine structures is not yet understood."

The key point, for me at least, is the estimate of the prominence plasma's density:
1016 to 1017 particles per cubic metre
If we take "particle" to mean "electron, proton or ion", and for the moment simplify the situation to just electrons and protons (but quite likely the exact behaviour and ionization states of other ions, especially helium, will be important or crucial to the full explanation) then we can say that these densities represent interparticle spacings, on average, between any proton or electron and its nearest proton or electron, of about:
4.6 to 2.2 microns
(This calculation is based on the simple notion of the particles being in a cubic lattice, where a 1 micron spacing is 1018 particles per metre3. For instance, 1016 means 1/100 of the particles per that same unit volume, with the spacing in microns being the cube-root of 100.)

Looking at the annotated NASA #Chart above (right-click this link and open in a new browser window, then use Alt-Tab, for Windows machines, to cycle between this and the new browser window) these densities are those of the top of the chromosphere, where the material is relatively highly ionized, but probably close to the threshold of density below which the plasma redshift process begins in earnest.  (I guess that my very approximate density threshold is about the same as that of Ari Brynjolfsson's theory, but his process also requires elevated temperatures, such as 200,000 K or so, before the effect begins to really work.)

Prominence material at 10,000 K is clearly ionized enough to be confined in magnetic flux tubes - but we might reasonably expect fractionation of ions, with the ions being confined and the neutral atoms escaping the field, and perhaps falling down towards the photosphere, as long as they are dense enough not to be supported or deflected upwards by any thin coronal plasma which is travelling upwards beneath them. 

When trying to understand the various solar, stellar, interstellar and intergalactic plasmas, one of the most important things to keep in mind is the propensity of a body of plasma, of given density and of given elemental composition, to radiate its heat energy - and how this changes with temperature and density.

There are various curves for "cooling function", "emissivity", "radiative loss" or whatever it is called for low-density plasmas of coronal composition, over temperatures 10,000 K to 10,000,000 K.  (To-do: find them and put some on this site!)  Generally, they have a dip somewhere around the 104 to 105 K area.  At lower temperatures, EUV and X-ray resonant line emmision from ionized heavy elements dominates the output.  At the higher temperatures, where all the nuclei are stripped bare - and there is no chance for electrons to settle in orbits and so emanate photons of precise energies as they fall into other orbits - thermal bremsstrahlung (free-free emission) dominates.  This leads to a situation in certain midrange temperatures where plasmas cannot cool themselves as much at certain temperatures as they can at higher or lower temperatures.  The temperatures of the transition region tend to be in this dip - so one would expect that if a body of plasma was subject to continual heating, its temperature would rise slowly (while at lower temperatures it can get rid of its heat radiatively) and then it would rise quickly in the temperature range where its emissivity is limited.  Once on the other side of the dip, the plasma would again radiate considerable energy and so tend to stabilise at some temperature, depending on the amount of energy being continually added. (To-do: research one of the key early papers and those which reference it: J. Raymond, D. P. Cox and B. W. Smith: .  Note 2004-05-10:  I am not so sure about this mid-temperature business - there are a variety of emmission curves and the ones I found don't seem to support this principle, though I am sure I have read it somewhere.)

This is one reason for little of the solar atmosphere being at the temperatures of the transition region - and this dip in the radiative loss curve is probably a factor making it hard for the cooler plasma in the prominences to be heated to the normal coronal temperature.   However, for now I will ignore this non-linear relationship between temperature and radiative loss, because I haven't had time to research it properly.  Also, with radiative loss in thin plasmas, we need to check that a thick slab of the plasma does not absorb its own radiation.  Plasma usually is optically thin at these wavelengths, which are usually in the EUV or X-ray ranges, so there is no problem getting rid of the energy, though to what degree this is true of very deep slabs such as intergalactic voids is another matter. 

The ability of the plasma to radiate its energy as EUV or X-rays is generally proportional to its density - or is it density squared, for the bremsstrahlung component which dominates at high temperatures?

This means that a cubic km of dense plasma, such as in a prominence, can radiate a far greater amount of energy, at a given temperature, than a plasma or coronal density at the same temperature.  Coronal plasma is ordinarily vastly hotter, but it seems that prominence plasma is capable of cooling the coronal plasma it touches, and so condensing the coronal plasma to add to its own volume of cool plasma.  How this occurs, given that this cooling contact presumably takes place across magnetic lines of flux which constrain both types of plasma, is an interesting question.

It seems that a second factor is probably at work in maintaining this remarkably cool state for such a large body of plasma, over such long times as days or weeks.  It seems that once the prominence plasma attains a low enough temperature and density, it is not heated as much as a corresponding volume of coronal plasma.  I haven't researched how strongly the magnetic fields constrain the prominence plasma - but it seems to be enough to hold it up against gravity, so there is presumably a similar sideways and downwards pressure from the sides and top of the flux tube. 

My rough hypothesis is that the main body of prominence plasma is dense enough to avoid most or effectively all plasma redshift, and that this, combined with the lower temperature leading to greater radiative loss (than somewhat higher temperatures) plus the greater density (due to the lower temperature and to some extent the magnetic confinement) leads to a plasma which is firstly not heated much and secondly is good at radiating its energy into space.   As long as this is the case, then it may cool and condense nearby coronal plasma.

If the magnetic field weakens, the prominence plasma may fall towards the photosphere.  If it remains dense, without magnetic confinement - which means that it is cannot be appreciably heated by contact with upwards moving coronal plasma - then it may fall back towards the upper chromosphere, which has about the same density and temperature.

However, if the magnetic field lines expand further away from the photosphere, they may weaken their hold on the prominence plasma and something else may happen - perhaps one or both of the following:
  1. The density of the prominence plasma is allowed to diminish, as the field weakens, and also perhaps as the surrounding pressure of the coronal plasma weakens.  As this increases the inter-particle spacing, the plasma becomes subject to significant plasma redshift heating, and so expands some more, leading to a positive feedback situation and the rapid heating and expansion of the entire body of plasma.  This would force the magnetic field wider and make it weaker, and soon the plasma would be "catching fire" and exploding in volume just like the material which rises through the transition region.  The result is the material expanding adiabatically, and probably being accelerated away from the sun by the deposition of momentum of the plasma redshift process.  Consequently the prominence erupts to form a coronal mass ejection.

  2. Also, the weakening hold of the extended magnetic flux tube means the prominence plasma is an appreciable distance from the photosphere.  If there is ordinary coronal plasma rising below it, then this coronal plasma will surely create a significant pressure upwards on the prominence plasma, heating it, stretching and weakening the magnetic flux tube, and so contributing to the processes which cause an eruption.
So perhaps the conditions for the survival of a prominence include some combination of:
  1. A strong enough and suitably shaped arrangement of magnetic flux tubes to support it against gravity, hold it close to the Sun against any pressure from underneath from fast-moving coronal plasma, and to stop the prominence plasma from leaking sideways along the flux tube in either direction.  (Though such leaks do not necessarily destroy the prominence - it seems they may remove some of the condensing material.)

  2. The potential for the "bathtub" of the magnetic support structure to let cooler, denser, plasma collect in the bottom of the trough, and perhaps fall downwards once it is cool and dense enough to be no longer so highly ionized, and therefore no longer so conductive and subject to magnetic confinement.  In this case, cooler plasma or partially ionized gas would rain downwards, and perhaps significantly protect the underbelly of the prominence from heating and outward acceleration by the coronal plasma which would ordinarily rise underneath it.

  3. Similar to the above point, but with neutral atoms falling out of the bottom as well, or instead.  This constitutes fractionation, so we would expect the elements with the highest FIP to drain out the bottom first.

I imagine theories such as these are well known.  But any theory of prominences must explain why the cooler, denser, plasma is so immune to the heating mechanisms which normally rapidly heat similar material entering at the transition region up to 1 or 2 million K in the corona. 

MHD theories of energy deposition need to explain this phenomena - the ability of either low temperatures and/or low densities to apparently greatly reduce the heating process.   My plasma redshift theory does this nicely - based on density alone.  The characteristics of prominence plasma fit reasonably well with my rough estimates for the density below which plasma redshift operates.  Ari Brynjolfsson's theory may make similar predictions about density, but it also (according to my limited understanding) would explain the prominence plasma being unheated due to the fact that it is nowhere near 200,000 K.

The ability of the prominence plasma to actively condense the surrounding coronal plasma might also be used as a case against the idea that the transition region is heated primarily by EUV coming down from the corona.  As I understand most MHD heating theories, there is little or no primary energy deposition in the transition region - and its unusually sharp temperature and density gradients are driven by:
  1. Energy coming down from the corona as EUV, which is progressively absorbed, heating the top of the transition region mainly, until there is none left (at least with energies above 10.6 eV) as we look further and further down into the chromosphere. 

  2. Possibly some direct "convection" heating from the hot corona - but how far do the particles travel?  The low corona is shooting outwards at a rapid rate.  This seems unlikely to me.

  3. The transition region begins at about the point (above the long stretch of approximately 6,000 K temperature, as shown in the NASA chart above typically existing at 1,600 to 1,900 km) where all the hydrogen atoms are ionized.  This may be something like latent heat of freezing, where a lot of energy goes into melting a block of ice, which remains at 0 degrees C until it is entirely melted, and then with the liquid water rising in temperature after that.

  4. The temperatures of the transition region generally being those where plasma cannot radiate its energy very rapidly, so it heats up and does not spend long at these temperatures.

(Have I forgotten any?  I am writing this from memory.)

So in most of the MHD theories of coronal heating, I think the low to mid corona is proposed as where the action really happens, with the transition region as a region underneath with an unusually acute temperature curve, due to the reasons listed above.

Apart from point 2, I tend to think these processes play a role.  But I still think that plasma redshift is the most likely explanation for the rapid heating which begins once the plasma's average inter-particle spacing gets above a critical point.  (It would be less in a hotter star, where the average wavelength and the coherence length of the photospheric light would be shorter.)

But consider point 1 - the downwards radiation of EUV, literally frying the cooler plasma and making it rise rapidly to a much higher temperature with a lower density.  This depends on the cooler, denser, plasma absorbing this EUV, which it apparently does to some extent.   But if this is the sole, or primary, reason for the rapid heating of the transition region, then why doesn't the same process rapidly heat the prominence plasma with about the same rapidity, vigour and consistency with which it rapidly heats the upper chromosphere at the transition region?

My tentative answer is that the EUV is not the primary source of heating in the transition region. (However, I believe that it may be a component, and contribute to the increasing temperature, and especially the increasing ionization, as we go down into the chromosphere.)  I suggest that the chromospheric material "catches fire" at the transition region because its density drops to the critical point where plasma redshift drives its density rapidly lower due to adiabatic expansion from heating, and also to some degree by lifting it away from the Sun with momentum deposition.  This happens all over the Sun, apart from the most disturbed region where flux tubes carrying plasma puncture the transition region.  This process does not rely on magnetic waves etc. (apart of course from sunlight, which are magnetic!) but is driven by plasma redshift.  The transition region only occurs where there is no magnetic confinement of the plasma.  (But the spicules may form in magnetic fields based in the photosphere which alter movement and pressure in some way which facilitates all the processes which constitute a spicule.)

So how does the edge of the prominence plasma escape being heated in the same way?  There must be some border zone between the hot ( approximately 1,000,000 K and beyond) large interparticle spacing ( approximately 100 micron) coronal plasma and the cool ( approximately 10,000 K), short interparticle spacing (4.6 to 2.2 microns) prominence plasma.  From all we know, this border is maintained by magnetic confinement.  This confinement does not stop EUV or sunlight, but it does tend to stop the flow of plasma across those lines of flux.  So here we have 100 to 1 ratios of temperature and 50 to 100 to 1 ratios of interparticle spacing, being close enough to (at least sometimes) allow cooling of the coronal plasma and its denser results adding to the prominence plasma.  But why is this zone not continually heated up by plasma redshift?   Wouldn't such a borderline area be subject to heating so that it would continually expand the border zone in a way which would stretch and weaken, or pass through (perhaps, slowly) the outer parts of the magnetic flux tubes?

In short: why don't the borders of the prominence plasma resemble the border of the chromosphere - the flaring expansion and heating of the transition region?  The answer is not obvious to me at present.  Prominences contain vast amounts of denser cooler plasma - of a kind which would normally be found in the upper chromosphere.  Why are they not fried by the primary heating mechanism - EUV or plasma redshift?  If the response is that the EUV is unimportant, then it is incumbent on an alternative theory, such as plasma redshift, to explain why the effect does not heat the borders of prominences.  Furthermore, the heating must be of such a limited extent as to allow the surrounding plasma to cool itself and condense!

Energy and mass of light encountered by each particle close to the Sun

While the temperatures attained by the solar corona, and the rapid heating of material rising through the transition region, is quite striking, these are very thin plasmas, by Earthly standards.  Conventional theories ignore the potential role of sunlight in this heating, but it should be remembered that the light is, by any standards, very bright indeed.  It is generally believed that scattering and free-free absorption have negligible effects on the plasma.  I haven't scrutinised this, and while I have suggested below that perhaps free-free absorption occurs differently than is predicted by current theories, in the remainder of this section I will concentrate on the role of my proposed plasma redshift effect in depositing energy and momentum in the solar transition region and corona. 

The peak energy density of sunlight is in the green-blue of the spectrum - let us say the average wavelength is about 0.5 um. 

Solar spectrum image shamelessly pinched from*sol_ukr*terskol*bmv_m.jpg

( The above image is from:  See: for a comparison of a Sun-like black-body spectrum superimposed with a coloured spectrum of what arrives on the surface of the Earth, after absorption in and above the photosphere, in the corona etc. and in the Earth's atmosphere.)

Thus, we can characterise the photospheric light as being an incoherent flux of photons, with a wide range of wavelengths, with most of the flux around an average wavelength of 0.5 um - at which each photon carries 2.5 electron volts of energy. (A 1.243 um photon carries one eV.  See: and .) 

The light is highly incoherent and at about 0.3 um and 0.9 um the flux is about 1/3 of the flux around 0.48 um.   Since coherence length is inversely proportional to the spectral width of the light, and proportional to the wavelength, I believe this is a very wide "spectral width" and that the coherence length is probably no more than 5 or 10 times the average wavelength.  So let us say the coherence length of sunlight is about 5 microns and the average wavelength is about 0.5 microns.

It is reasonable to think of wavefronts passing near a particle being affected on distance scales approximating that of the wavelength - so expect the wavefront of sunlight to be affected (as in the dimple diagram above: #Dimple-diagram) primarily at distances of 0.5 to 1.0 um or so from the particle.

If we consider a lone electron, proton, alpha particle or heavier ion, some distance away from other particles (say at least 5 or 10 microns) then we can think of the wavefront of light (which would manifest eventually as a single photon if we chose to absorb it somewhere) travelling in a vacuum.  I would say that we can ignore the influence of nearby particles, since they are all further away then both the wavelength and the coherence length.  So we assume the wavefront is travelling at full vacuum light-speed when it encounters the electron, proton or ion.

If we conservatively estimate an approximately 0.5 um range from the particle where the wavefront will be slowed, deformed or whatever, then we can imagine a circular zone of about 1 um diameter where the sunlight is affected by the particle.  For simplicity, let us consider this as a 1 um square area. 

The flux per square metre of photosphere is about 64 Megawatts.  This is 64 watts per square millimetre and 64 microwatts per square micron.  Thus, for a particle (electron, proton etc.) in the chromosphere, transition region or low corona, we can roughly estimate that there is 64 microwatts of sunlight streaming through the approximately 1 um2 area we theorise is affected by the particle (this is 64 micro-Joules per second).  With about 1356 watts per square metre of sunlight reaching the Earth, 64 microwatts is the amount of sunlight which would come through a hole in a piece of aluminium foil, of diameter 0.244 mm.  (Sanity check: 1 um x Earth's orbital radius / solar radius approximately equals 214 um.)

Here I look at some energies of this situation, in electron volts, converting both the masses of particles and the energy of photons into electron volts.
Mass of electron = 5.1 x 105 eV ( )
Mass of proton =  9.4 x 108 eV

64 micro-Joules = 4 x 1014  eV

64 microwatts as number of 0.5 um, 2.5 eV photons per second = 1.6 x 1014
64 microwatts as masses of electrons per second = 7.8 x 1012
64 microwatts as masses of protons per second = 4.2 x 105
Thus, it can be seen that each lone electron or proton is tangling, perhaps ever so slightly, with something much stronger and more energetic than itself: sunlight.

The NASA chart above shows that the density of plasma at about 5,000 km (the low corona, where the temperature is about 1,000,000 K and rising rapidly) is about 10-17 grams per cubic cm.  This is 10-11 grams per cubic metre and since the material is primarily protons (1.67 x 10-24 grams) and electrons (9.1 x 10-28 grams), for our discussion we will conclude that the cubic metre contains 6 x 1012 protons and the same number of electrons.  Each of these 1.2 x 1013 particles occupies, on average, 8.3 x 104 cubic microns.  This volume is equivalent to a cube of about 43 microns on each side.  Thus, at this sort of interparticle spacing, the conditions for my plasma redshift process are clearly established.  (I can imagine plasma redshift occurring to a limited extent with an interparticle spacing 1/20th of this, which is a density 8,000 times greater - about the 10-13 grams / cm3 level, which is precisely in the middle of the transition region, where the material seems to "catch fire" and begin its rapid expansion and heating.  See also the discussion below on element fractionation, and how the process could occur with sparsely spaced ions in a denser neutral gas.)

Let us consider a cubic metre of space in the low corona, 5,000 km above the photosphere, with 6 x 1012 protons and the same number of electrons.  There is 64 Mega-Joules per second passing through it (while the light comes from the side, as well as below, for simplicity we assume it is entering from the bottom of the cube and exiting from the top).  This process takes 1/300,000,000 second, so the light contained in this cubic metre at any one time is (6.4 x 107 / 3 x 108) = 0.21 Joules, which is 1.3 x 1018 electron volts.

(In the following, I use conversions between mass in grams and energy in megawatt hours and electron volts.  An electron's mass-energy is 5.11 x 105eV.  An electron, at rest, has a mass of  9.11 x 10-28 grams, so the mass-energy of a gram of electrons or anything else is  5.11 / 9.11 x 1033= 5.60 x 1032 eV.  This is 8.97 x 1013 Joules.  A megawatt-hour is 3.6 x 109 Joules so this the mass-energy of a gram is 24,916 Megawatt hours.  Looking at my electricity bill, I find this to be worth Australian 3.5 million dollars . . . )
Converting this to electron volts and the masses of electrons and protons, we find that the cubic metre contains:
6 x 1012 protons
6 x 1012 electrons
Which have a mass of  10-11 grams
and a mass-energy of  5.6 x 1021 eV
 Light energy:
0.21 joules
1.3 x 1018 electron volts
Which is 1/4,307 of the mass-energy of the protons and electrons = 2.3 x 10-15 grams
(I don't accept the notion that light has no mass.  Shine a torch in a closed spaceship and the total mass of the spaceship doesn't change, yet the torch loses mass and whatever absorbs the light, a few nanoseconds later, gains it - so the light must have mass.)

So we have some idea of the relative mass-energy density of the low corona - the proton and electron rest masses are 4,307 times greater than the mess-energy of the light which is ripping through them in little wavefronts only about 5 to 10 microns thick.

In the low corona, heating estimates per proton are in the range 0.01 to 1 eV per second as mentioned below in the quote from page 256 of Steven Cranmer's review paper.  (I have not scrutinized these, but as noted above, perhaps the higher estimates include concentrated, but spatially rare, active events in the corona, rather than a typical value found in the polar or equatorial coronal holes.)

In the extended corona, at 2 solar radii (1.5 radii above the photosphere) the rate of about 0.1 eV per second is estimated (page 259).  At this altitude, the Sun subtends 0.5 radian in the sky, so the flux is considerably less than close to the photosphere.  (To-do: calculate how much less light is received here than close to the photosphere.)  Each particle is arguably interacting, albeit very slightly, with 1.6 x 1014 photons each of about 2.5 eV per second.  So we only need an effect which redshifts each photon in the order of one part in 4 x 1014 (1/400,000,000,000,000) per interaction to achieve 1 eV per second.  (This 1 eV s-1 is a very crude estimate, perhaps including energy deposition rates in active regions, not in the polar and equatorial coronal holes - and it is just for protons, not counting electrons or ions.)

I don't yet have any quantitative theoretical basis for estimating the strength of the proposed plasma redshift effect, but if for the moment we accept a rate of redshift per proton interaction of about 10-15 , then we can arrive at an approximate density for the Void IGM, assuming that the same process there shifts light one part in 13.2 billion per light year.
Redshift per light year = 7.57 x 10-11 .
Redshift per proton = 10-15 .
Protons encountered per light year for a photon, which interacts with protons in about a 1um square area around its path (imagine the photon travelling in a straight line, as if it were a particle) = 1.3 x 103 .

So this is the number of protons we might find in a volume measuring 1 um x 1um x 1 lightyear.  The volume is 10-6 x 10-6 x 9.46 x 1015 = 104 metres3

This gives a density of 0.13 protons per cubic metre in the Void IGM, which seems rather low.  However, all conventional theories about the Void IGM are based on Big Bang cosmologies, and people who have estimated 440 Mega K temperatures for the Void IGM find it hard to believe these estimates, because there is no mechanism in the Big Bang theory of the Universe to heat the IGM to such temperatures.  Also, this calculation I am doing here is based entirely on a 1 eV per second heating rate in the solar corona, which is on the high side of the figures quoted by Steven Cranmer.  Calculating from a lower heating rate would give less redshift per photon-proton interaction, and lead to a higher estimate for the density of the Void IGM.

Since this plasma is so low in density, its particles rarely interact to create free-free emission, so its ability to radiate its heat is very limited indeed.  Perhaps it could rise to a high enough temperature of hundreds of millions or above a billion K (in so doing, making the electrons relativistic and so probably leading to electron-positron pair-production) to exert enough pressure, even at this very low density, to press against the intra-cluster IGM and the galaxies which are gravitationally and frictionally coupled to it, into the shapes we see in the galaxy redshift surveys.  (See discussion below on large-scale structure of the Universe.)

Dramatic events in the transition region?

The transition region is only about 200 km thick. In and around it there are extreme changes in temperature and density - such as from 6,000 K to 500,000 K.  As far as I know, the best observations make it difficult to be confident about exactly what is happening in the transition region.  However, some theorists have created models of densities, pressures, temperatures and velocities which, to some degree of approximation, are supposedly consistent with the observations.  One such model is:
A Model for the Chromosphere-Corona Transition Region Based on Radio Observations and on Hydrodynamical Conservation Equations
Lantos, P.
Solar Physics, Vol. 22, p.387 (1972)
This is for the quiet sun (quiet solar atmosphere), in the area between spicules.

However this model does not seem to be self-consistent, since at each level, such as between 2035 and 2105 km, the electron density (and therefore the amount of matter) multiplied by the velocity at each level (it is stated to be the "upwards velocity") results in a range of figures between 12.6 and 47.3, whereas for a constant upward flow of matter in a parallel stream, the product of density and velocity should be constant at all altitudes. 
The figures in this paper, Table 1, indicate explosive acceleration. 

For instance imagining a parcel of plasma at 2035 km, we take its velocity as 4 km s-1so at t=1 seconds we consider it to be at 2040 km.  There it has a velocity of 10 km s-1 so at t=2 seconds we consider it to be at 2050 km.  Likewise at t=3 seconds we find it at 2070 km and at t=4 seconds, near the end of the model at 2100 km.  So it seems that the parcel has gained 37 km per second (4 to 41) in 4 seconds, which is an acceleration of about 1000 G. 

Also, the model predicts, at 2100 km, a plasma containing (approximately) 1.2 x 109 pairs of protons and electrons, at 41 km a second.  If this were the case, then the flow of matter for each square cm would be 1.2 x 109 x 4.1 x 106  = 4.9 x 1015 hydrogen atoms (ignoring helium etc.)  That equates to a flow in grams per second of 8.13 x 10-9 .   But this is 40 times higher than the rate of 2 x 10-10 grams given for coronal holes in the NRL Plasma Formulary detailed in the next section, and 400 times the value given for the quiet sun, tpwhich this model supposedly applies.

I read this paper in early 2003, assuming that the velocity figures were realistic - and decided that things were indeed dramatic in the transition region.  Now, April 2004, I see the figures are way out of line with currently accepted interpretations of observations.  There is a dramatic heating and acceleration process taking place in the transition region, but not this dramatic!

AdsAbs' citations list leads to another paper, also concerning the quiet sun (p 115):
A Dynamical Model for the Chromosphere-Corona Transition Region
Chiuderi, C.; Riani, I.
Solar Physics, Vol. 34, p.113   (1974)
which critiques the Lantos paper along similar lines (p 119): the velocity and flow rates are far too high.  In the Chiuderi - Riani model, velocities are far lower, and only reach 1km s-1 at 100,000 km above the photosphere.  The flux of material is (p 118) 8.08 x 1012 hydrogen atoms per second per square cm.  This is 1.35 x 10-11 grams per second, which is close to the figure of 1.35 x 10-11 listed in the NRL Plasma Formulary (below).  I have a feeling this model of the transition region is too soft and extended.  I would like to see such figures for a coronal hole, which has ten times the flow rate.

Another paper which tabulates temperature, density, pressure and "velocity" is:
Structure of the solar chromosphere. III - Models of the EUV brightness components of the quiet-sun
Vernazza, J. E.; Avrett, E. H.; Loeser, R.  (AKA "VAL".)
Astrophysical Journal Supplement Series, vol. 45, Apr. 1981, p. 635-725.
However, this is for the quiet sun, rather than the coronal holes where the fastest, least complicated, least impeded heating and acceleration take place - and where the volume of matter per cm2 rising, on average, to the corona and solar wind is ten times that of quiet sun regions.

I was going to find some figures which show temperature and density changing over altitude in the transition region, and then calculate for each altitude what the average upwards velocity must be, based on the mass-loss per cm2 to feed the solar wind.  But I have run out of time, and I am perplexed that the "velocity" in the first paper above, and the "micro-velocity" in the second (Tables 10 to 15) do not seem to fit with my understanding of the velocity and density at all altitudes multiplying to the same value.

To-do: Take the temperatures and densities from one of the VAL models, over the range 2,141 to 2,439 km and compute: upwards velocity for the coronal hole flow rate of 2 x 10-10 grams flowing past each cm2 per second.  Then calculate the acceleration rate.  A quick look indicates moderate upwards velocities, such as (Model A), 2,345 km, approximately 104 cm s-1 which means much lower acceleration rates than I had previously thought.  What is "micro-velocity"?  Perhaps it is turbulence from the theorized wave heating mechanism.  Am I completely misunderstanding the relationship between velocity, local density and the total amount of matter travelling, on average, upwards?

Coronal heating and solar wind acceleration - how much energy is required?

(Rewritten 2004 April 27.)

Here is a quote from pages 233 - 234 of "The Solar Corona" (Leon Golub and Jay M. Pasachoff 1997 - see details in the Resources section below):
"The total power emitted in x-rays is only [approximately] 10-6 of the Sun's bolometric [total output at all wavelengths] luminosity.  Even taking into account all of the coronal energy loss mechanisms, which include radiation over all wavelengths, solar wind and other mass outflow (such as mass ejections; see Ch 10.3), heat conduction both outward to interplanetary space and inward to the lower portions of the atmosphere, the total energy budget is still only [approximately] 10-4 of the Sun's total output.  (See also the proceedings of a meeting devoted to Mechanisms of Chromospheric and Coronal Heating (Ulmshneider et al. 1991), and the review article by Tsuneta (1996) in Tsinganos (1996).)"
These last references are to the book Solar and Astrophysical Magnetohydrodynamic Flows .

Here is some information from a page of solar physics parameters:
The NRL Plasma Formulary (2002)

concerning the chromosphere and corona, apparently from G. L. Withbroe and R. W. Noyes, Mass and Energy Flow in the Solar
Chromosphere and Corona, Ann. Rev. Astrophys. 15, 363 (1977), which does not appear to be on the Net.

Parameter (Units)        Quiet     Coronal    Active
                         Sun       Hole       Region

Chromospheric radiation
losses (erg cm-2 s-1)
  Low chromosphere      2 x 106    2 x 106        > 107
  Middle chromosphere 
  2 x 106    2 x 106           107
  Upper chromosphere    3 x 105    3 x 105       2 x 106
4 x 106    4 x 106    > 2 x 107

Transition layer
pressure (dyne cm-2)        0.2        0.07           2    

Coronal temperature
(K) at 1.1 solar
radii (70,000 km)      1.1 to         
106      2.5 x 106      
                       1.6 x 106

Coronal energy losses
(erg cm-2 s-1)
2 x 105    6 x 104      105 to 107
  Radiation               105        104         5 x 106 
  Solar Wind        <5 x 104    7 x 105          <  105
  Total               3 x 105    8 x 105             107

Solar wind mass loss
(g cm-2 s-1)         <2 x 10-11 
2 x 10-10   <4 x 10-11   

Before discussing the energy requirements, here are two sidenotes:
I hadn't heard of these differing transition region pressures before.  To what extent can they be reliably measured?  If the pressures do vary over this 28:1 range, then how does the temperature vary?  If plasma redshift is the key source of heating in the transition region - and the "transition region" is defined as that point at the top of the chromosphere where rapid heating, expansion and upwards acceleration begins, then we would expect that the crucial determinant of this process starting would be the inter-particle spacing.  For a fixed interparticle spacing, with a 28:1 range of pressures, we would expect a similar 28:1 range of temperatures (ignoring the temperature dependence of ionization, and therefore whether the material is atoms or split into a greater number of particles).  Temperatures and densities vary enormously in the transition region - which is very thin and generally beyond the ability of telescopes to resolve adequately.  A good test of the plasma redshift theory would be to show whether the pressure at the transition regions above various parts of the Sun are correlated with temperature there, so that that the density, and therefore inter-particle spacing is about the same in all three types of transition region.

While the solar wind is a powerful, important and highly energetic phenomena, the quantity of matter it involves is exceedingly small.  The total mass loss of 1.37 x 1012 g s-1 (as referenced below) works out, over the photospheric surface of the Sun (6.09 x 1022 cm2), to an average of 2.2 x 10-11 grams per square cm per second.   (Coronal holes have ten times this rate per square cm, but these areas probably only cover 10 to 15% of the surface, on average.)  Assuming the density of the photosphere is 5 x 10-7 g cm-3 (from the NASA chart, the density varies greatly, and Google finds a wide range of estimates) then how long does this mass loss take to use up a centimetre of the photosphere?  About 20,000 seconds.  How long would this rate of loss take to use a centimetre of hydrogen gas (H2 = 9 x 10-5 g cm-3) at Earth's atmospheric pressure?  4 x 106 seconds = 46 days. 

Also from the above page, the total radiant power of the Sun is rated at 3.83 x 1033 ergs s-1.

On 2004 April 26 I reconsidered the question of how much energy we might expect from a plasma redshift process, if it is to explain most of the energy of the key phenomena.  This is on the basis that the major heating and accelerating phenomena are not currently adequately explained and with the assumption that a single process, such as plasma redshift (which may involve one, two or more separate processes) does explain it. 

The probability that only one new mechanism, or type of mechanism, remains to be discovered is less than 1.0. When debugging a faulty piece of electronic equipment on the assumption that there is only one fault, a great deal of time can be wasted when it turns out that the errant  behaviour was the product of two or more faults!  But researchers have spent several decades applying all currently recognised physical principles to the problem, without success.  I think the answer is most likely to lie in a small number of previously ignored processes - most likely one, but perhaps two or more.

The key energy budgets are as follows, expressed as a proportion of the total solar energy output listed above: 3.83 x 1033 ergs s-1.
Lifting the solar wind against the Sun's gravity, say, to 1AU and accelerating it to the velocities observed.   The solar wind mass loss is here assumed to be 1.37 x 109 kg s-1 (Peter D. Noerdlinger: citing A. J. Hundhausen, in Cosmic Winds and the Heliosphere .)  This is 1.37 x 1012 grams per second.
The escape velocity from the photosphere is 618 km s-1 and the escape velocity from Earth's orbit (1AU) is 1.414 x Earth's orbital velocity, 1.414 x 29.78 = 42 km s-1 .  So to get the solar wind out to 1AU with no extra velocity, the energy required is the same as accelerating it to 618 - 42 = 576 km s-1 = 5.76 x 107 cm s-1.

The wind's velocity at 1AU varies considerably, and the fast and slow solar winds have different densities.  For this approximate calculation, I choose 724 km s-1 as a midpoint between 400 (slow) and 750 (fast) solar winds, as measured in the ecliptic, since most of the wind, averaged over all angles from the Sun, is fast.  I also chose this to make the sum of the two accelerations be a convenient 1,300 km s-1, and to ensure that we are not underestimating the energy required.  This is 1/230 the speed of light.

So every second some process or combination of processes does the equivalent of accelerating 1.37 x 1012 grams of matter to 1.3 x 108 cm s-1

The energy required is (1/2 x mass x velocity2):

0.5 x 1.37 x 1012 x (1.3 x 108)2 
= 6.85 x 1011 x 1.69 x 1016 
= 1.16 x 1028 ergs s-1 (1.16 x 1021 watts)
This is 3.02 x 10-6 of the Sun's total energy output = 3 parts per million.
Note that this figure is sensitive to any error I made in estimating an "average" velocity  - what we really need is an average kinetic energy, since working out energy from average velocity squared will lead to an underestimate.  Do my figures really account for the energy in coronal mass ejections?

(Also, what if some of this energy results from momentum coupled to particles as photons are either absorbed (by some currently unrecognised process) or redshifted?  Coupling a particular amount of momentum to a heavy particle like a proton (where perhaps more plasma redshift occurs than with an electron) results in less kinetic energy than if it was coupled to a lighter particle - and electron.)
Kinetic energy in the solar wind particles which is random, and therefore counted as "temperature" compared to whatever is judged to be its average velocity.
(To-do: figure this out properly, but if the figure below is even approximately accurate, then it is insignificant in the final result.)

This is tricky to measure or even to define, since the wind is largely collisionless and so is not a fluid, but a poorly connected set of particles with various velocities.  I will do a very rough estimate of this, but perhaps this is erroneous.  From Figure 3 of Steven Cranmer's review paper (above) I estimate the proton temperature at 1AU to be 2 x 105 K.  Ignoring the heavier ions which may be more than ten times hotter, and the electrons, I calculate the average kinetic energy per proton is 3/2 x Boltzmann's constant x temperature. 
Average energy per proton in ergs = 1.5 x 1.38 x 10-16 x 2 x 105
= 3.84 x 10-11
Now I want to multiply this by the (very approximate, ignoring helium nuclei) number of protons leaving the Sun per second:
Solar mass loss = 1.37 x 1012 g s-1
Mass of proton = 1.67 x 10-24 grams
Number of protons per second in solar wind = 8.2 x 1035
Total thermal energy in the solar wind going past 1AU 3.84 x 10-11 x 8.2 x 1035
= 3.14 x 1025 ergs s-1
This is 8.2 x 10-9 of the Sun's total energy output = 0.008 parts per million.

Energy radiated by plasma in the regions from the high chromosphere to wherever at the top of the corona where it effectively stops radiating due to it becoming collisionless. 

Looking at the above figures from the NRL Plasma Formulary and ignoring for the moment the active regions, we see coronal radiation for the quiet sun (equatorial but non-active) and coronal hole (I guess typically polar, but also at lower latitudes at times) as being 105 and 104 ergs per second per square cm of the photospheric surface, respectively.  Since the flux of light per square cm of photosphere is 6.28 x 1010ergs per second, I estimate the radiative losses as a fraction of total solar output:

Quiet sun: 1.68 x 10-7 = 0.168 parts per million
Coronal hole: 1.68 x 10-8 = 0.0168 parts per million
(How much of this radiation is to interplanetary space and how much goes back to heat the material in the chromosphere and transition region?)

But this ignores the active regions, where the coronal plasma is, in places, vastly hotter and so radiates a huge amount of EUV, X-rays and gamma-rays - estimated above to be 50 times the rate for the quiet sun.  From these figures I don't know what proportion of the Sun's atmosphere is "active" - which makes sense since this varies enormously through the solar cycle.
I have ignored some other forms of energy dissipation such as the wind affecting planets, comets, dust and atoms, ions and other particles from outside the solar system.

According to the above calculations, the total energy requirement to lift all the material from the photosphere out to 1AU, give it the temperature and velocity we find there, and account for the energy radiated by the quiet sun regions or coronal holes, would be about 3 parts per million of the total solar output.  Most of this would be deposited in the transition region and corona, since it seems that there is only relatively minor heating and acceleration in the solar wind.

So where do these higher estimates come from, such as the 10-4 in this sentence from the above-quoted passage from Golub and Pasachoff's book?
"Even taking into account all of the coronal energy loss mechanisms, which include radiation over all wavelengths, solar wind and other mass outflow (such as mass ejections; see Ch 10.3), heat conduction both outward to interplanetary space and inward to the lower portions of the atmosphere, the total energy budget is still only 10-4 of the Sun's total output."
It seems this includes the energy of coronal mass ejections, which may not be properly covered in my mass and velocity calculations above, as well as the radiation from the active regions, which are much more luminous in EUV, X-rays and gamma rays than quiet sun or coronal hole regions.

This is a very loose figure of 10-4 - probably a safe upper bound, rather than an accurate estimate of total energy required for all the heating and accelerative processes we are trying to understand.

If we could find a good agreement between the energy of all the processes we theorise are driven wholly or primarily by plasma redshift, and the observed redshift of light from the Sun, then the theory would have passed a major and easily understood test.  However this is not the case - and the situation is not so simple.

The currently unexplained (or inadequately explained) heating and acceleration processes in the solar atmosphere are not uniformly distributed.  I think the transition region phenomena seems to be pretty consistent, but perhaps it too varies in its nature considerably between coronal holes, quiet sun and active regions.  Certainly the heating and acceleration of flares and coronal mass ejections are vast, and so we wouldn't expect the total energy budget of the unexplained processes to be evenly observable in the redshift of all light we receive at Earth from the photosphere. 

But even allowing for a minimal estimate of energy required for heating and acceleration, if we are to think of plasma redshift as providing most of the energy, it seems we are looking for average redshifts of 3 or more parts per million.  Here I am only discussing my theory, such as it is.  Ari Brynjolfsson's paper includes a mechanism for accelerating the solar wind (and I guess lifting material through the transition region and corona) which is not based on plasma redshift.  He proposes a diamagnetic acceleration process for this. 

The next section continues the discussion about the energy requirements for my theory and the fact that they are not, currently, observed as redshifts in photospheric absorption lines.

Why isn't the required redshift observed?

If redshift of photospheric absorption lines had been observed in a way which correlated with the energy dissipated by coronal heating, acceleration etc. then a theory such as plasma redshift would have been pursued long ago.  

But what if the redshift process does shift the main continuum of photospheric light, powering the heating and acceleration we are seeking to explain, but does not appreciably redshift the absorption lines?
It would be easy to dismiss plasma redshift entirely, or at least in respect of significant heating and acceleration in the solar atmosphere, on the basis that no such redshift is observed.  However this would be dismissing a promising theory based on a particular theory alone.  That particular theory is that any such redshift process, which draws energy from all the "photons" which pass through the plasma, must also shift the absorption lines.  While I think there are several avenues to reliably establishing the existence of plasma redshift, I think that any plasma redshift theory needs to propose one or more reasons why absorption lines are not redshifted as much as the main continuum, at least in the solar observations we know about so far.

Before making any such proposal, here is a little discussion about the observed redshifts. 

Redshift measurements of photospheric light is not, as far as I know, achieved by looking for a shift in the entire black-body Planck curve spectrum.  That is very broad, and I expect it would be firstly impossible to reliably measure a few parts per million shift in its overall spectrum, and secondly impossible to know to that accuracy what the real spectrum would be at the photosphere, before it was subject to redshift in the corona.  Therefore, all our measurements of redshift of photospheric light rely on the shift (with respect to light sources on Earth, perhaps corrected for any differing conditions in the photosphere) of lines of light - very narrow wavelengths corresponding to particular energy levels of electrons in atoms or ions (or, in principle, molecules, but I don't think there are many in the photosphere). 

Generally these lines are absorption lines - rather than emission lines.

First let us consider emission lines.  Since an emission line consists of light created by a highly resonant process, I would expect its coherence length (the all-important length of the wavefront of each "photon") to be long, such as several cm or perhaps metres.  In any event, such lengths would greatly exceed the average inter-particle distances in the plasma of interest - the transition region, corona and most or all of the solar wind out to 1AU.  Therefore, I would predict that plasma redshift (according to my theory and I think to Ari Brynjolfsson's) would not redshift such lines to any appreciable degree.

Assuming we can't measure parts per million redshift in the Planck curve itself, this leaves the redshift of photospheric absorption lines as our only likely way of measuring the proposed redshift of sunlight in the transition region and corona.  (Also, as suggested by Ari Brynjolfsson, we could look for redshift in the light of a star for which the line of sight passes through the low corona, during an eclipse.  As far as I know, he does expect absorption lines to be shifted along with the continuum.)

At first blush (what's the latin for this?) since an absorption line is an absence of light, bordered at adjacent wavelengths by unaltered photospheric light, one would expect that shifting the entire photospheric light would also shift the absorption lines.  Below I develop some ideas as to why this might not occur.

The observations about the redshift of solar photospheric lines might be important to plasma redshift in two ways.  Firstly, if it can be shown that light travelling straight up from the photosphere undergoes a particular redshift, compared to a reference wavelength on Earth, then we can consider it to be the sum of gravitational redshift, plasma redshift in this particular section of the atmosphere, and any conditions affecting the original nature of the absorption line in the photosphere.  Secondly, even if there are uncertainties about these conditions, observing a different redshift at the limb of the Sun's disk, compared to that at the centre, might constitute evidence of plasma redshift, since the light at the limb is travelling obliquely through a layer of plasma and so is therefore likely to be subject to more plasma redshift.

I have a large stack of papers (about 1,000 pages) on the redshift of photospheric lines, and in particular how they vary across the disk, leading to various limb effects.  It is a controversy which continues to this day, and which seems to have begun early in the 20th century, at least in English, with a paper from 1916, in the Indian Kodaikanal Observatory Bulletin XLIX, which the library there has kindly provided me with a photocopy of:
On the Change of the Wave-length of the Iron Lines in Passing From the Centre of the Sun's Disc to the Limb
J. Evershed and T. Royds
(March 2006: This is available as a PDF: ../refs/solar-redshift/ where I list some additional papers not discussed below.)

Probably the initial paper is:
ber eine bisher unbekannte Verschiebung der Fraunhoferschen Linien des Sonnenspektrums
Halm, J. Astronomische Nachrichten, volume 173, p.273
The full PDF is available, but I can't understand German.  The citations to this paper continue to recent years.  (The citations system at AdsAbs is a brilliant tool for finding all pertinent articles to this or many other questions.)

Also, for anyone wishing to investigate this field, a good reference would be the work by Klaus Hentschel ( on the history of this controversy.  This includes his Habilitation Thesis 1995 "Interplay of Instrumentation, Experiment and Theory (with case studies on redshift in the solar spectrum, 1880-1960)" (  Also, his article:
The Conversion of St. John: A Case Study on the Interplay of Theory and Experiment
Klaus Hentschel,
Science in Context 6 1 (1993) pages 137 - 194.

One widely referred to paper is by Madge Adam of Oxford (Margaret Gertrude Adam whose 2001 obituary is here:,12212,750210,00.html ) who made very accurate measurements of photospheric absorption line redshifts at various positions across the disk and to the limb.  This paper, and another related one by L. A. Higgs are both cited in Ari Brynjolfsson's paper:
A new determination of the centre to limb change in solar wave-lengths
Adam, M. G.  
Monthly Notices of the Royal Astronomical Society, Vol. 119, p 460 to 474
The Solar Red-Shift
Higgs, L. A.
Monthly Notices of the Royal Astronomical Society, Vol. 121, p. 421-435

This controversy, which I have only a very limited grasp on, involves questions such as:
Looking for, and not finding (as far as I know) the redshift expected due to gravitational redshift of photons ascending from the photosphere to Earth against the Sun's gravity.

Redshift of light observed at the centre of the disk due to the Doppler effects of outflows in the region where the absorption takes place. (There must be inflows and outflows balancing each other in or near the photosphere, since the net amount of matter lost to the solar wind is a minuscule volume at photospheric or low chromospheric densities.  Therefore, the flow of material upwards in a condition of absorbing light, probably in a way which light is absorbed differently in the downflowing currents, due to different temperatures and therefore ionization state.) 

Similarly Doppler effects at the limb, due to sideways movement of material which we tend to observe more when it is coming towards us than when it is going away from us.  This raises all sorts of questions about granulation, convection, optical depth of various types of material in various structures . . .

Subtle effects on the wavelength of the absorption due to the atom or ion being affected by temperature, pressure, bombardment by other atoms etc. - and how this might manifest in different observations when viewing directly towards the photosphere compared to across it, at or near the limb.

Likewise, subtle effects on the wings of absorption lines, including differing optical depths at slightly different wavelengths, which affect the centre and limb observations differently.

Rotation of the sun causing Doppler shift - and uncertainties in correcting for this.

When measuring the limb at the poles, movement of absorbing material towards of away from Earth due to a variety of mechanisms.

If a large proportion of the acceleration and/or heating can be explained with a process other than plasma redshift, then perhaps we are only looking for a small redshift which might arguably be observed in the photospheric lines.  Perhaps, for instance, there is some aspect of absorption ("free free absorption" I guess) which is currently not recognised, by which ordinary photospheric "photons" are absorbed by the plasma in the transition region, corona and solar wind, delivering heat and momentum.  Perhaps, as Ari Brynjolfsson suggests, magnetic effects are largely responsible for lifting and accelerating the material away from the Sun.

I will assume, for the purposes of this discussion:
There is a plasma redshift process, relying on the wavefront thickness (AKA "coherence length") of the affected light being smaller than the average inter-particle density of the plasma.

This redshift process powers most of the heating and acceleration phenomena of the solar transition region, corona and solar wind, requiring, for instance 3 x 10-6 of the Sun's output, and therefore resulting in this much redshift.

That we do not observe this sort of redshift in the photospheric lines.

That we do observe plasma redshift in photospheric lines of distant stars (and likewise of the continuum and emission lines of all luminous objects, including radio, probably UV and perhaps X-ray wavelengths) - due to that redshift being produced in very low density Void IGM where the inter-particle spacing generally exceeds the wavefront thickness of these absorption or emission lines.
As noted above, I would not expect there to be plasma redshift of photospheric (or low chromospheric) emission lines due to plasma redshift, since the wavefront thickness of those lines is greater than the average inter-particle distance of the bulk of the plasma the light travels through on its way to Earth.

So the key question becomes:
How could the black-body continuum be redshifted by 3 or more parts per million (arguably many times this if the light is passing through an active region where more redshifting plasma is confined than would be the case in quiescent corona), without us observing anything like this redshift (possibly no redshift at all) in the absorption lines which were in that light before it passed through the redshifting plasma.

Here we are getting into quantum mechanics - so to expect a concrete, nuts-and-bolts physically intuitive answer is probably unrealistic.

One argument would be that an absorption line is just like an emission line - it is a highly coherent characteristic of the electromagnetic radiation, and as such is not affected by the coronal plasma, due to its long coherence length.   This makes some sense, if one accepts that the valid answers to quantum mechanical questions resemble little more than number games.  It seems they do, so perhaps this is as good an explanation as we are likely to get!

Another argument might be that the edges of the absorption lines are highly coherent light - not just absence of light - and that as such, the "photons" of that light have long coherence lengths and so escape being redshifted.  This seems pretty reasonable - and is more physically intuitive, for me at least.   We can start with highly incoherent light, such as from a black-body radiator, and filter it to create highly coherent light.  The absorbing atoms or ions do exactly this, so they are creating a coherent component of what we observe as an otherwise incoherent black-body spectrum.  If we start asking ourselves exactly what are the characteristics of these different sets of photons, then we are probably making a mistake.  I think that the notion of "photons" is deceptive.  We can talk about them after the energy has been deposited somewhere - when the so-called photon has ceased to exist.  We can think about all the barriers, reflections, probabilities etc. which guided the "photon" from its source (which we can identify, perhaps down to the location of an individual atom) and its destination, which we can also precisely identify.  But we can't talk with any precision or wisdom about a "photon" while it is travelling from one place to another.

I can't give a physically intuitive, solid explanation of why plasma redshift of the Sun's light would not result in redshift of the absorption lines.  But I can't give any such explanation for two slit interference either.  Critics of my plasma redshift theory or Ari Brynjolfsson's cannot give a solid explanation of two-slit interference of light, or of matter (such as helium atoms), so I respectfully suggest that any such critics allow for the possibility that the absence of redshift in the photospheric absorption lines may have a perfectly good explanation (by quantum mechanical standards) in the event that plasma redshift is shown experimentally to occur.  It seems that the theories of conventional physics can't explain the heating of the corona etc. and can't explain the Universe and quasars without serious contradictions (of theory and observations).  Since plasma redshift seems to be such a promising basis for explaining all this, I think it makes sense to cut the theory some slack for a while, regarding the lack of redshift of solar photospheric absorption lines.

Revisiting Free-Free Absorption?

Please see the above section for why it may not be necessary to propose a new aspect of  Free-Free Absorption.  For now, I have made this section grey. 


Free-free absorption (FFA) is where a photon is absorbed, and its energy and momentum conveyed to, two charged particles which begin and end the interaction as free particles.  By contrast, bound free absorption is a photon taking an electron out of an atom.  Free-free absorption involves, typically, an electron travelling near a proton (or positive ion) and when it gets close, the photon is absorbed by the pair (not just by the electron, I think, despite what is often written) with the electron getting most of the energy and being accelerated away from the proton faster than it approached it.  A single charged particle can't, normally, absorb a photon, because there's nowhere for the energy to go, other than kinetic motion, and that motion would involve a momentum change which is impossible for an isolated particle.  Free-free absorption involves two (or more, I guess) particles so that one can kick against the other as it develops the new velocity with which it absorbs the photon's energy.  It does not involve resonances, so the relationship between wavelength and absorption is relatively smooth, compared to absorption processes involving atoms or molecules.

I am (was . . . ) investigating "free-free absorption" (FFA), AKA "reverse bremsstrahlung", because I wonder if a revised understanding of this could explain most of the coronal heating and acceleration.   A difficulty with the plasma redshift process as the sole source of this energy deposition is that (according to some widely accepted estimates) we see a much smaller redshift in the absorption (and emission) lines than should happen with the redshift which would account for the heating.

The million degree temperature to which the corona rises very rapidly (within a few thousand kilometres of the photosphere) is deeply counter-intuitive, because if it were a black-body, it could not get hotter than the surface of the Sun.  But low-density plasmas are anything but a black body radiator / absorber.  They radiate less energy at higher temperatures, especially when they are hot enough to strip the electrons of all the nuclei, so there are no atomic resonance absorption systems in the soup - it is purely protons, electrons and bare nuclei flying around.

If there was a mechanism by which plasma could absorb photons, most particularly once it reached an average interparticle spacing comparable to or greater than the wavelength and/or the coherence length of the light, then this would explain firstly the heating of the transition region and corona, and secondly the outward acceleration of the particles, due to the photon's momentum coupling to the particles which absorb them. 

My feeling, in October 2003, is that a proper analysis of Free-Free Absorption will show that in addition to its general trend of dropping off at shorter wavelengths (I am yet to find out why it does - or why it is thought that it does) it will be found that there is a marked increase in absorption in a situation such as the transition region and low corona: when photons (perhaps necessarily of short coherence length) pass through plasma where the inter-particle distance is about the same as the wavelength, and or greater than that wavelength to some degree.

I have lots of stuff to dig back into to find out what current theory says about Free-Free Absorption.  It is a bit of a backwater, and is usually assumed to be the symmetrical companion of Free-Free Emission.

I think that there is a profoundly important physical process here which has been overlooked.

There's a lot of material to be found on free-free emission / absorption, and to various "Gaunt factors" (quantum-mechanical corrections to classical formulae, especially regarding free-free processes 1993AAS...182.8104G) which apply in different situations.  For instance 1998MNRAS.300..321S Accurate free-free Gaunt factors for astrophysical plasmas - Sutherland, Ralph S.

I won't say much more about my theory here, because I have many things to research and much work to do on it, but please write to me if you would like to discuss it.  I am researching the transition region, coronal heating and acceleration, the solar wind, the history of tired light theories, redshift of photospheric and other solar lines at the limb of the Sun compared the centre of the disc (first discovered in 1907 by J. Halm) and of course quantum mechanics and relativity. 

Combining the catalogues of the 2dF surveys

I am also very interested in quasar - galaxy clustering.  I am preparing to analyse the 2dF surveys - using the separate datasets of the QSO and Galaxy surveys:

In December 2003 I completed some C++ code which combined the two catalogues into a single text file, which can be easily read into an array in RAM.  Also, I created a "Nearest Neighbour" data set, which can be quickly read into RAM (for each object) to show which other objects are nearby, sorted by distance, and with their orientation pre-computed too.  However, before serious analysis can be done, I also need to integrate the "completeness" masks for both surveys.  The "completeness mask" tells, for each position in the sky, what proportion of the input catalogue was properly observed and turned into information about galaxies and quasars.  Without this, it is impossible to know where the borders of the survey are, and there are all sorts of problems in trying to measure clustering and other proximity patterns of galaxies and quasars.  Please let me know if you want this C++ code and/or the resulting data.  In principle, it should be possible to search this data for galaxy -> quasar and quasar -> quasar pairs, and then to use their spectra to look for the Transverse Proximity Effect, as discussed below.  I don't intend to pursue this, since other researchers seem to have done this thoroughly and have so far failed to find substantial evidence for this effect existing. 

The program can also be used to do easily written C++ statistical analysis of the key characteristics of the galaxies, Narrow Emission Line Galaxiess and quasars, such as:

   Lowest bin starts at:   -0.1000
   Bin width:               0.1000
   Number of bins:              38
   Last bin ends at :       5.0000

Redshift    Galaxies        NELGs           Quasars        
bin         Number  % of    Number  % of    Number  % of   
                    214211            4608           23660 

  -0.1000   3671  1.7137       0  0.0000       0  0.0000 
   0.0000  89802 41.9222     464 10.0694       0  0.0000 
   0.1000 102345 47.7777    1069 23.1988      46  0.1944 
   0.2000  17708  8.2666    1346 29.2101     170  0.7185 
   0.3000    554  0.2586    1020 22.1354     381  1.6103 
   0.4000     26  0.0121     473 10.2648     583  2.4641 
   0.5000     25  0.0117     156  3.3854     796  3.3643 
   0.6000      4  0.0019      48  1.0417     944  3.9899 
   0.7000      4  0.0019      19  0.4123     965  4.0786 
   0.8000      3  0.0014       5  0.1085    1030  4.3533 
   0.9000      6  0.0028       5  0.1085    1079  4.5604 
   1.0000      4  0.0019       3  0.0651    1109  4.6872 
   1.1000      3  0.0014       0  0.0000    1191  5.0338 
   1.2000      2  0.0009       0  0.0000    1258  5.3170 
   1.3000      4  0.0019       0  0.0000    1254  5.3001 
   1.4000      3  0.0014       0  0.0000    1329  5.6171 
   1.5000      4  0.0019       0  0.0000    1426  6.0271 
   1.6000      2  0.0009       0  0.0000    1345  5.6847 
   1.7000      6  0.0028       0  0.0000    1302  5.5030 
   1.8000      2  0.0009       0  0.0000    1279  5.4057 
   1.9000      2  0.0009       0  0.0000    1165  4.9239 
   2.0000      3  0.0014       0  0.0000    1019  4.3068 
   2.1000      4  0.0019       0  0.0000    1034  4.3702 
   2.2000      5  0.0023       0  0.0000     791  3.3432 
   2.3000      5  0.0023       0  0.0000     596  2.5190 
   2.4000      2  0.0009       0  0.0000     558  2.3584 
   2.5000      1  0.0005       0  0.0000     402  1.6991 
   2.6000      2  0.0009       0  0.0000     309  1.3060 
   2.7000      2  0.0009       0  0.0000     166  0.7016 
   2.8000      0  0.0000       0  0.0000      90  0.3804 
   2.9000      3  0.0014       0  0.0000      24  0.1014 
   3.0000      2  0.0009       0  0.0000      11  0.0465 
   3.1000      0  0.0000       0  0.0000       4  0.0169 
   3.2000      0  0.0000       0  0.0000       2  0.0085 
   3.3000      0  0.0000       0  0.0000       0  0.0000 
   3.4000      2  0.0009       0  0.0000       0  0.0000 
   3.5000      0  0.0000       0  0.0000       1  0.0042 
   3.6000      0  0.0000       0  0.0000       0  0.0000 
   3.7000      0  0.0000       0  0.0000       0  0.0000 
   3.8000      0  0.0000       0  0.0000       1  0.0042 

I have more such statistics on a separate page: 2dF-redshift-stats.txt .  It is interesting to see the distribution of redshifts, such as thousands of galaxies which are recorded with redshifts between -0.01 and +0.01 in what appears to be a statistical cluster.  I haven't looked at this in detail to see to what extent this may be an artifact of the process, rather than a real observation.  However I have no reason to suspect that the data is systematically wrong for so many galaxies.

The Cosmic Microwave Background radiation and black dwarfs

(Note, I am following the convention revealed by Google that the plural of astrophysical "dwarf" is "dwarfs" rather than "dwarves". )

I discuss this topic in the introduction, which was written after the following.

Note added 2006-09-08:
In 2006 some research was prominently reported as a challenge to the Big Bang Theory.
"Either it (the microwave background) isn't coming from behind the clusters, which means the Big Bang is blown away, or ... there is something else going on," said Lieu.
The paper is:
The Sunyaev-Zel'dovich effect in a sample of 31 clusters - a comparison between the X-ray predicted and WMAP observed CMB temperature decrement
Richard Lieu, Jonathan P.D. Mittaz, Shuang-Nan Zhang
ApJ v648, p176 (2006).

From the abstract:
Although our comparison between the detected and expected SZE levels is subject to a margin of error, the fact remains that the average observed SZE {Sunyaev-Zeldovich Effect} depth and profile are consistent with those of the primary CMB anisotropy , i.e. in principle the average WMAP temperature decrement among the 31 rich clusters is too shallow to accomodate any extra effect like the SZE.
The Researchers use published X-ray emission and WMAP data to research how much a random sample of 31 galaxy clusters shield us from the CMB.  The BBT says the CMB comes from beyond any such clusters, and it is widely accepted that the plasma in the clusters should alter or attenuate the CMB which passes through it.

A search for papers by Lieu and Mittaz reveals quite a number which look interesting to me.

From the Science Daily article, Richard Lieu is also quoted as saying:

"One possibility is to say the clusters themselves are microwave emitting sources, either from an embedded point source or from a halo of microwave-emitting material that is part of the cluster environment.

"Based on all that we know about radiation sources and halos around clusters, however, you wouldn't expect to see this kind of emission. And it would be implausible to suggest that several clusters could all emit microwaves at just the right frequency and intensity to match the cosmic background radiation."

However, if we forget the BBT limit on galaxy ages and assume they are very old indeed, then we can easily imagine a large number of black dwarfs and their collision byproducts radiating the CMB, as I describe below.

Also, some research on MACHOs - dark (or too dim to see) objects of mass comparable to the Sun, which can be detected indirectly by their gravitational lensing of stars in our galaxy or in nearby galaxies, including especially the Large Magellanic Cloud.
Microlensing towards LMC: a study of the LMC halo contribution
S. Calchi Novati, F. De Luca, Ph. Jetzer, G. Scarpetta
Accepted for publication in Astronomy & Astrophysics (Submitted to 2006-07-16.)
They conclude that the observed microlensing is most probably caused by objects with fractional solar mass, in the range of 0.1 to 0.3 solar masses.

I have not tried to estimate how many of these object would be required to provide the mass required in galaxy halos.  I suggest that there could be a lot of them, and that their smaller collision byproducts could be hard to detect, since they are smaller than stars.  This smaller size lead to generally unobservable brightening of a distant star due to gravitational lensing and to only a very minimal and brief reduction of the distant star's light on the very rare occasions where one gets in between our telescope and a distant star. 

Note added 2004-05-10:
The idea of the CMB coming from brown/black dwarfs has been suggested before, as I imagine many of the ideas here have been.  A good place to start might be this article, its references and those articles which cite it:
Dark matter and brown dwarfs - Prospects for the direct detection of a brown dwarf halo
Daly, Ruth A.(; McLaughlin, Gail C.
ApJ, 390, no. 2, p. 423-430, May 10, 1992

A more recent paper with observations which may relate to my proposal - but in this case observations of white dwarfs - is:
Direct Detection of Galactic Halo Dark Matter
Ben R. Oppenheimer, Nigel C. Hambly, Andrew P. Digby,
Simon T. Hodgkin and Didier Saumon
Science, Vol. 292, pp. 698-702 (27 April 2001)
There are 61 references to this article.  The original article and related papers are available at Ben R. Oppenheimer's page:  . Use the "White Dwarfs" link to: . (Papers are accessible via the red links.  Some papers are gzipped Postscript, see: #PostScript-PDF. )

The Cosmic Microwave Background Radiation is often cited as proof of the Big Bang.  To me, this seems contrived and extremely unlikely.  Without looking into it in detail, I would have thought that Free Free Absorption in our Galaxy and in the IGM would attenuate the CMB sufficiently for us to be sure that what we observe has not been travelling through space, without change, for 15 billion years or more. 

One possibility may be that the CMB is black-body radiation from a whole bunch of black dwarfs (black dwarves - black dwarf) - collapsed stars which have cooled to the average (radiant, for black-body radiators and absorbers) temperature of space, which I understand is around the 2.7 K temperature of the CMB.  Similarly it could be lots of dust grains, or solid objects somewhere between dust grains (which can be 0.1 um or less) and the sizes of black dwarfs, which I guess is measured in kilometres, to hundreds or thousands of kilometres.   This includes solid fragments of black dwarfs etc. caused by their collisions.   (But to behave as a black-body radiator of microwaves such as those of the CMB, I would expect the objects to be of sizes measured in centimetres or tens of centimetres at least.)

I include in black dwarves neutron stars which have stopped spinning appreciably (so they are not radiating more energy than they absorb), and all other collapsed stars apart from black holes.  Conventional Big Bang theory states that there can't be many black dwarfs, because the Universe is too young for collapsed stars to have cooled so far - but I think the Big Bang theory will be proven to be false.  (This doesn't mean I have any idea how or why the Universe is comparatively static, or how it came into being.)  Brown dwarfs (too small to form stars which fuse hydrogen) could also feature in the following discussion, but I think they would be too large and have too low a density - so they would be subject to tidal forces and tend to join together over time, rather than be flung into further orbits as I suggest below.

Maybe these black dwarfs constitute a large part of the "dark matter" which is believed (with good reason, I think) to form a spherical cloud (sometimes called a halo) in which each spiral galaxy is embedded.  (Elliptical galaxies?)  How could this occur?  We have no real understanding of galaxy formation or of basic orbital behavior of galaxy constituents, so we need to keep our minds open.  After stars below a certain mass collapse, and with sufficient passage of time (apparently far in excess of 15 billion years) we expect them to become small, dense, cold black dwarfs which initially follow the trajectory of the star. 

I can imagine how such hard, compact objects will, over long periods of time, become flung out into relatively random elliptical orbits in all orientations, of a vaguely similar diameter to the optically visible galaxy but at all varieties of orientation.  (I am thinking of spiral galaxies here - ellipicals already have their stars in such randomly scattered orbits.) 

Here's an idea on how this might occur.  Let us say two ordinary, optically radiant, hydrogen (etc.) burning stars come really close to each other in the galaxy.  They would not behave like billiard balls - they would torn apart to some extent by tidal forces - their gravitational interaction is inelastic and would result in one or both stars losing mass, to the other star and/or to the interstellar medium.  Because their gravitational interaction is not highly efficient, they will lose some of their kinetic energy and momentum, and generally be unlikely to be flung far into orbits very different from their original orbit.  This means that in spiral galaxies (ignoring ellipticals and globular clusters for the moment) ordinary stars only survive if they are all rotating roughly together, not whizzing past each other - which means they must be in a disk.  But objects such as black dwarfs (including neutron stars), which are not subject to destruction or losing mass in close (tidal) interactions, could survive close interactions with other black dwarfs and, over time, be flung into randomly oriented orbits which have nothing to do with the circular plane of movement which most stars inhabit.  The probability of one or both black dwarfs in normal stellar population circular orbits flinging one or both of themselves into orbits with totally different orientations (that is, into the roughly spherical cloud of dark-matter in which the visible galaxy is imbedded) is small, but once it happens, the flung object is highly unlikely to return to an orbit resembling its original circular, (visible) galactic plane one.  Since we have no obvious time constraints in this model - there being no reason to believe the Universe is rapidly expanding or is as young as 15 billion years or so, it is sufficient for their to be a slow, but generally one-way process of flinging hard, compact, objects into non-galactic plane orbits to explain how a visibly spiral galaxy would become embedded in a similarly sized, or generally larger, roughly spherical cloud of such objects, in randomly oriented generally elliptical orbits.

Black dwarfs are small, solid objects which are not subject to tidal forces (unless perhaps there is an extraordinarily close encounter, bordering on a collision).  They could have gravitational interactions with other black dwarfs which were highly efficient in terms of conserving energy - and so they could progressively fling themselves into elliptical orbits, with a steady state being achieved when they are generally so far away from each other, in all sorts of randomly oriented orbits (especially elliptical orbits) that the probability of close interactions with other black dwarfs is minimised.  Also, black dwarfs could be flung into different orbits by gravitational interactions with stars. They may disrupt the star with tidal forces, but the black dwarf itself would remain just as it was, with at most a moderate addition or loss of mass.

Such black dwarfs would be observable only by gravitational lensing or occultation of a very distant star or quasar. They may be too small to make any significant change to the observed light of any star or quasar they get in the way of, unless that star is thousands or millions of times more distant from us than the black dwarf.   If many of these black dwarfs (including neutron stars) have been smashed (over hundreds of billions of years or more) into smaller chunks, then this would make them harder to observe (with occultation or gravitational lensing of stars / quasars) but it would increase the total surface area they have - and therefore lead to a stronger 2.7 Kelvin black-body radiation field - the Cosmic Microwave Background.

Maybe there's a cloud (AKA "halo") of black dwarfs, somewhat or greatly larger than our Galaxy.  Maybe this extends to merge with similar clouds of the Small and Large Magellanic Clouds.  Maybe these clouds of black dwarves extend to the size of galaxy clusters, to some extent at least.  Given time, the furthest extent of the clouds would grow and a small proportion of them would be ejected from the main clouds in which each visible galaxy is embedded - just as with liquid water in air, some molecules acquire sufficient velocity to break free and become vapour in the air. 

This doesn't happen with stars, gas planets or comets because these would be ripped apart in the close encounters which give black dwarfs such altered trajectories.  Likewise, galaxies can't be ejected from clusters via close gravitational encounters with other galaxies or anything else (such as a large black hole), because the tidal forces would destroy them as unified structures.

Maybe the black dwarfs, and the Intra Cluster Medium (the intergalactic plasma between galaxies in a cluster, as distinct from that in the voids between clusters) constitutes most of the mass of the clusters.  

Once it is accepted that galaxies and their clusters are far older than 15 billion years, then the potentially huge numbers of black dwarfs and their fragments could account for the "dark matter" apparent spherical "halo" of mass surrounding spiral galaxies - whilst also explaining the CMB.

By the way, the Sunyaev-Zeldovich Effect (AKA  "Sunayev-Zeldovich") - which is the CMB seeming to be slightly "hotter" when looking towards galaxy clusters, supposedly due to CMB being altered by the inter-cluster medium - could also be explained by the CMB emanating from the cluster being not plasma redshifted at that point compared to a slight plasma redshift of CMB coming from galaxies etc. behind the cluster.  Ned Wright explains the observations and the conventional explanation at: .

Plasma redshift, the Inter Galactic Medium, Voids and Galaxy Clusters

Here are some thoughts I have been considering since late 2003.  The really short version is:

Plasma redshift heats the Inter Cluster Medium (in the voids) to such high temperatures, and with very low densities, that the resulting pressure corrals the denser, cooler Intra-Cluster Medium into its observed configuration - resembling bubble-like roughly spherical voids confining clusters of galaxies in sheets and filaments just as air bubbles confine soapy water.

I discuss this in the introduction, and in several sections below.  Sorry this is badly structured.

The X-Ray Background Radiation

Here are some references:
Field, G. B.; Perrenod, S. C. 1977 Constraints on a dense hot intergalactic medium. ApJ vol. 215, Aug. 1, 1977, p. 717-722.   1977ApJ...215..717F

A model is proposed in which exploding galaxies heat the intergalactic gas (IGG) to a temperature of 100 million to 1 billion K. The thermal bremsstrahlung from the model agrees with spectral measurements of the X-ray background (XRB). It is shown that recent submillimeter measurements of the cosmic microwave background (CMB) are consistent with a spectrum distorted from blackbody by Compton scattering on the same IGG. It is also shown that the isotropy and intensity of the XRB rule out its origin from discrete gas clouds. Because of the large energy requirement to heat the IGG and other considerations, the existence of a cosmologically significant amount of hot IGG must be regarded as uncertain. It is concluded that the amount of hot IGG corresponds to a critical density parameter of no more than 1.0.

Marshall, F. E. et al. 1980  The diffuse X-ray background spectrum from 3 to 50 keV. ApJ vol. 235, Jan. 1, 1980, p. 4-10. 1980ApJ...235....4M .

The spectrum of the extragalactic diffuse X-ray background has been measured with the GSFC Cosmic X-ray Experiment on HEAO 1 for regions of the sky away from known point sources and more than 20 deg from the galactic plane. A total exposure of 80 sq m-s-sr is available at present. Free-free emission from an optically thin plasma of 40 plus or minus 5 keV provides an excellent description of the observed spectrum from 3 to 50 keV. This spectral shape is confirmed by measurements from five separate layers of three independent detectors. With an estimated absolute precision of about 10%, the intensity of the emission at 10keV is 3.2 keV/keV/sq cm/s/sr, a value consistent with the average of previously reported spectra. A uniform hot intergalactic medium of approximately 36% of the closure density of the universe would produce such a flux, although nonuniform models indicating less total matter are probably more realistic.

Ajit K. Kembhavi and Jayant V. Narlikar 1999 Quasars and Active Galactic Nuclei, Cambridge University Press.  Pages 335 - 343. (The X-ray Background - XRB).

The picture which emerges from the above is:

Field and Perrenod quote Kellog, E. M 1974 in X-Ray Astronomy, ed. R. Giacconi and H. Gursky (Boston: Reidel): the intra-cluster gas is around 108 K (100 Mega K).

Satellite X-ray observations establish with considerable accuracy the existence of a spectrum of background X-rays in the photon energy regions 3 to 50 keV.  Below 3 or so keV, the contribution of individual X-ray fluxes from quasars is apparently significant, but quasar spectra roll off and are thought to make little significant contribution to shorter wavelengths.  Galactic (our galaxy) sources and absorption are insignificant at wavelengths shorter those of 0.5 keV X-ray photons.

The highly isotropic nature of this 3 to 50 keV XRB makes it reasonable to conclude that its source lies beyond our Galaxy - in the void IGM as well as potentially in other galaxies, extra-galactic sources (quasars, perhaps, but not in ways we currently observe), in the Cluster IGM of clusters and in the dark matter around galaxies which is presumably at least partially distributed through clusters.

Marshall et al. and Kembhavi and Narlikar report the temperature required of the IGM (presumably the Void IGM) not in Kelvin, but in units of the kinetic energy of the particles.  They also refer to the IGM as "gas", as does Field and Perrenod.  But the IGM is clearly a plasma, which is not everyone's idea of a "gas".

Field and Perrenod are more up-front about the temperature of a plasma which would give rise to the observed 3 to 50 keV XRB spectrum - that temperature, they calculate, is 4.4 x 1010 K.  This is worth spelling out in full:  440,000,000 K.  Such extraordinarily high temperatures are inexplicable in the standard Big Bang theory - which generally tries to explain such high temperatures as resulting from an earlier epoch of many supernovae.  This is the usual approach to explain things which seem odd - "the Universe was very different at an earlier stage of evolution".

Field and Perrenod conduct a brief investigation of the idea that the source of the XRB is not the IGM in general (implicitly the Void IGM) but a large number of smaller clouds of plasma. They consider 2 x 106 such clouds as being needed to provided the observed smoothness of the observations, and from this deduce sizes of those clouds and their luminosity.  They conclude (without considering heating and potential cooling of such smaller clouds - which is another problem for such a theory) that such smaller clouds could only produce the observed flux if their densities were so high as would produce observably different radiation.  They decisively reject any such notion, and conclude that the observations can only, apparently, be explained by the IGM, in general (and therefore in the great majority of the volume of the observable Universe) is at a temperature of bout 440 Mega Kelvin.

The authors of all three references above are operating on the basis of the Big Bang - Expanding Universe theories as if they were facts. (Though Kembhavi and Narlikar have final chapters which considers challenges to this, and occasionally point out how much easier it would be to explain the observations of quasars, radio galaxies etc. if they really were not as far as the conventional interpretation of their redshift implies.)

All these authors conclude that the extreme difficulty of explaining the heating of the IGM to these prodigious temperatures makes the existence of such temperatures tentative, or even less likely.  This seems to be at odds with proper scientific method - which is to have greater respect for observations than for existing theories - recognising that there is an unknown amount of important stuff we do not yet know.

Field and Perrenod can see no means by which the IGM could be heated like this in the Universe here and now, and assume it must have been heated at earlier stages of evolution.  Even then, they can find no mechanism which comes close to explaining it.  They cannot see how radiant energy from galaxies or quasars could perform the task, and the notion of shock-front heating (as often invoked to explain Mega Kelvin "coronal" plasmas in our Galaxy) evidently is not worth considering.  They consider the possibility of galaxies exploding (at an earlier stage of their evolution, such as when they may all go through a "quasar stage") and conclude that the galaxies, in general, would have to heat the IGM by ejecting a considerable portion of their mass at speeds approximating 30% the speed of light.  It is impossible for me to understand a galaxy doing this and still remaining a galaxy afterwards, whatever energy source is invoked to drive this prodigious ejection.

The Void and Cluster IGM

I haven't followed the latest research in this field.  The following discussion is based on several reasonable conclusions which can be reached from the observations:
  1. The only obvious explanation for the observed (via Doppler redshift) orbital velocities of the visible stars in spiral galaxies (ellipicals as well?) is that most of the mass of a galaxy is in "dark matter" - distributed in a roughly spherical cloud at least as large as the visible galaxy.  In this discussion, I pass over any exotic states of matter, including neutrinos, and assume the "dark matter" is made up of ordinary matter in the form of plasma, dust grains, black dwarfs, and perhaps in unusual isolated instances, gaseous matter cool enough to form clouds of atomic hydrogen (or at least areas cool enough for such atoms to occasionally form).

  2. The largest-scale structure we have been able to observe in the Universe is a bubble-like arrangement of extremely transparent voids, seemingly pushing outwards to neighbouring voids, confining between them denser areas we identify as galaxy clusters and super-clusters.  For illustrations and text, see: , and .

  3. The Cluster IGM is around 100 Mega Kelvin.  No-one knows why.

  4. The Void IGM is around 440 Mega Kelvin.  No-one knows why - especially since it seems to be putting out prodigious power, and is nowhere near any galaxies.

One explanation of the heating of these plasmas could be the energy deposition caused by plasma redshift in the average Void IGM - such as photons in the visible range losing 1 part in 13,200,000,000 of their energy per light-year - which is cosmological redshift of 70 km/sec per Mega parsec.

Thus, the passage of starlight (and also microwaves, UV, X-rays etc.) through both the Void IGM and Cluster IGM, with all photons (at least in the most luminous wavelengths around 1 to 0.2 microns) being subject to plasma redshift, could be the mechanism which heats the IGM continually and so provides the power for the XRB.

Low density plasmas are totally unlike black-body radiators.  Once they attain temperatures where all electrons are stripped from the nuclei of constituent atoms (leaving mainly electrons, protons and helium nuclei) their ability to radiate away their thermal energy gets less with increasing temperature.  (See  Radiative cooling of a low-density plasma, Raymond, J. C.; Cox, D. P.; Smith, B. W.  1976 ApJ 204: 290-292  )

Let us suppose that the Void IGM does continually receive prodigious quantities of energy by slightly redshifting the starlight which passes through it.  How else could it get rid of that energy except by Free Free Emission (thermal bremsstrahlung)?  As far as we know, it can't very well cool itself by physical contact with neighbouring matter, since the distances (tens and hundreds of millions of light years) are so vast and the IGM so low in density.

Large scale structure of the Universe

(Added 2008-11-03.)  See the Fingers-of-God and large voids in this image from SDSS: .

(New introductory paragraphs and important link added 2004-05-10.)

Be sure to see the rotating "3D" animation of the CfA galaxy redshift survey at:
It is by far the best visualisation I have found of the void / bubble / foam / filament structure.  I suggest loading the "original data" and clicking "Play" and then "faster".  Then switch to the "enhanced structures" data and press "Play" and "faster" again.  This latter set concentrates on the most dense areas. 

To me, its really obvious that galaxies are not in the circular orbital patterns of gravitational motion as found in galaxies and stellar systems.  The only obvious principle which could explain what we see is that the voids are the dominant force in the Universe - empty, but containing sufficient pressure to corral most or all galaxies.  (The location of quasars is hard to know, since a lot of their redshift is intrinsic to their local IGM.  The abovementioned images show only galaxy locations.  Maybe quasars are not always confined like galaxies.)  This leads to two questions:
How could the void, which is clearly of exceedingly low density, exert such pressure? 
Assuming we don't invoke unconventional forces, particles etc. the only answer seems to be that it must be exceedingly hot - vastly hotter than stars or conventional heating processes could make it.
How could such a thin Void IGM, even if it was so hot and had sufficient pressure, corral things as heavy and hard to push as a star or a galaxy?
This is a challenging question, but I suggest it pushes higher density, cooler Intra-Cluster IGM and that this is coupled gravitationally and/or by friction to the galaxies (the full galaxy and its currently not understood dark matter halo).
(End of new intro.)

The bubble-like - or foam-like - structure observed in galaxy clusters and intergalactic voids is well established.  It is deduced from observing galaxies according to their redshift.  To a first approximation, I believe that redshift (of galaxies, not quasars, BL Lacs etc.) is a measure of distance - though the continuing uncertainty about the "Hubble constant" shows how variable the relation is, or at least how hard it is to measure reliably even if distance is a direct function of redshift.  (Consider also the "Finger of God" aspect of galaxy redshift survey maps - I (and Ari Brynjolfsson) think this is caused by a cluster of galaxies having the rear ones appear more redshifted than the front ones, due to more plasma redshift, primarily in the denser plasma in the cluster.  If this is the case, then only a small amount of "Finger of God" will be caused by random (+ and -) velocities of the galaxies, and most of it will be positive redshift caused by local plasma redshift.)

This foam-like arrangement is difficult or impossible to explain from a Big Bang perspective.  One aspect of this is that it is a pattern which is a complete departure from the planetary structure of matter on smaller scales.   At the level of atoms, solar systems and galaxies we have the same paradigm - central mass with orbiting smaller masses, attracted by the electromagnetic force or gravity.  To some extent, I think we see the effects of gravity in clusters - but the clusters themselves do not seem to be circular or have a planetary structure.  From all accounts, galaxy structures are elongated and irregular.  Their really large-scale structure reveals them to be like the rubber in foam rubber - where the voids are like the empty bubbles in the foam.

Consequently we must conclude (tentatively, of course, since we don't know what we don't know) that there is a more powerful force at work here than the gravitational attraction of galaxies at the very large inter-cluster distances.

The Void IGM has been established to be extraordinarily transparent, and relatively extremely free of atomic hydrogen.  One estimate of the maximum possible density of H I (atomic hydrogen) in the IGM, based on the observed absence of atomic hydrogen absorption lines, is one atom of H per cubic kilometre.   (I have a reference for this somewhere.)

We may reasonably conclude that the Void IGM is extremely low density, since it does not seem to condense or collapse under its own gravity.  Nor does it seem to draw clusters of galaxies into the voids themselves.

The virtually complete absence of atomic hydrogen (which can only exist at temperatures below about 10,000 K), together with the reasonably derived implications of the X-ray Background Radiation, leads us to pursue hypotheses compatible with the notion that the Void IGM is at the prodigiously high temperature of about 440 Mega Kelvin.  (Exactly how it apparently stabilises at this temperature is a question for further research, once we have a hypothesis about its nature and heating mechanism.)

Whatever its density, a temperature of 440 Mega Kelvin gives the Void IGM a considerable capacity to exert pressure on whatever constrains it, even with its presumably very low density.

It is evident that galaxy clusters contain most of the mass of the Universe, and that they are squashed into their shapes by the pressure of the vast, very approximately spherical, volumes of the Universe we know as intergalactic voids.

The lower temperature of the denser Cluster IGM is explicable by the greater capacity of a denser plasma to radiate its thermal energy.  (There are other considerations I won't pursue at present regarding the optical depth of such large bodies of plasma at these X-ray wavelengths, and any others which would occur with Free Free Absorption - suffice to say that we assume that both the Void IGM and Cluster IGM slabs of plasma are optically thin, even with their vast dimensions, to the X-ray emissions we observe, and which evidently form the primary means by which they rid themselves of energy they are somehow continually collecting.)

According to my plasma redshift theory (and, as much as I understand it, Ari Brynjolfsson's) for a given average wavelength of light, of a given intensity, the capacity of a fixed volume of low-density plasma (one in which the interparticle distance exceeds the wavelength, or probably more importantly the wavefront thickness, AKA "coherence length" of the light) to redshift the light, and therefore to absorb energy from that light, is proportional to its density.  For instance, assuming that the plasma redshift of starlight (say the sum of the Planck black-body curves of galaxies of stars of temperatures from 3,000 to 30,000 K) occurs in a plasma with average inter-particle distances of 1 cm. then a cubic metre of plasma with this density will absorb and redshift 1,000 times as much as a similar plasma with an average particle spacing of 10 cm.

I am ignoring the possible effects of temperature on the plasma redshift process - and other considerations such as magnetic field.  My currently limited imagination of the mechanism has no place for those, but Ari Brynjolfsson's theory involves a great deal of temperature dependence and some dependence on magnetic field.   Perhaps increasing temperature of the plasma acts to limit its capacity to redshift the light.  I will assume it doesn't.

Now I will propose a possible mass distribution theory of the Universe.  This involves no assumption of expansion or rapid overall change - where "rapid" means anything shorter than 100 billion years or so.  I assume that for reasons unknown the structure is reasonably stable for very long periods of time - say hundreds or thousands of billions of years - so it is not in a state of flux.  Big Bang cosmologies imply that everything is changing, and that when we observe galaxies which are, say, 5 billion light years distant, we are also looking back to an epoch when everywhere, including where we are now, was very different since the Universe and all its constituent structures were less "evolved" (in the Big Bang theory, this means the change in form over time since the Big Bang, not the biological notion of natural or sexual selection) than at present.   I have no idea how the Universe formed, or how it may be relatively static.  But until there is evidence to the contrary, I will assume that any overall change in its nature, or the structure of its constituents, is far slower than in an Big Bang cosmology, and may well be beyond our ability to observe.

The bulk of the mass of the Universe is contained in galaxy clusters - even though these occupy maybe 1 or 2 percent of the volume of the Universe.

The radiant energy output of the optically luminous objects is driven by fusion of light elements in stars, and by gravitational collapse, as in black holes (and therefore quasars, AGNs etc.) and neutron stars (their rotating magnetic fields are powered by past collapse of the star).   Novae and supernovae also contribute to the flux of electromagnetic radiation - these are special instances of stellar fusion.

Stars radiate most of their energy around optical wavelengths.

Immediately this light leaves the star, at least in stars like the Sun, some of this energy is redshifted by the low-density plasma in the corona, and this gives rise to million K temperatures.  The energy lost by the photons gives the coronal plasma (AKA solar wind particles) enough momentum to escape the star's gravity.  Consequently, stars are constantly evaporating a small proportion of their mass into the interstellar medium.  (Stars with large abundances of heavier elements, which retain electrons around their nuclei at higher temperatures than hydrogen or helium, have atmospheres which absorb a significant proportion of the star's light.  The resulting momentum drives much denser stellar winds, stripping such stars of a great deal of their outer mass in a relatively short time.)

Some or most of this stellar wind, together with some or most of the debris of novae and supernovae, eventually collapses under gravity (perhaps with shocks from supernovae, and or tidal forces such as in spiral galaxy arms - and/or waves of supernovae going around galaxies and looking like arms  . . . ) to form new stars.  But some of it also is ejected beyond the galaxy, accelerated by the momentum of the light it either absorbs or redshifts, against the galaxy's gravitational attraction.  (This can be seen simply as an extension of the corona / stellar wind of each star, but continuing to scales larger than the galaxy, with all such flows mixing together.)

Therefore, galaxies develop a plasma (or occasionally, perhaps, in places, atomic gas) cloud in which they are embedded.  (There are various questions here about equilibrium of radiant pressure vs. gravity.) 

Perhaps, as suggested above, after tens or hundreds or thousands of billions of years, the collapsed stars form so many black dwarves that these add to the invisible dark matter cloud, or halo, in which the galaxy is generally centred.  (I have no ideas at all about the origin of globular clusters and their randomly oriented elliptical orbits!  This discussion is primarily about spiral galaxies.  Maybe elliptical galaxies are in a state where the stellar rotating disc has degenerated via collisions and somehow the whole system has stopped spinning like a disk, and flung all stars into elliptical orbits.)

So a (spiral) galaxy, on its own in space, would consist of a large diffuse randomly orbiting cloud of dark matter - cold (say 2.7K) black dwarfs, constituting perhaps a substantial fraction, probably the majority, of the total mass and plasma, generally heated, as observed, to 100 Mega K, by - as best we know - plasma redshift or some similar process.

The optically visible (spiral) galaxy then is a small, central, part of entire greater galaxy structure - and constitutes probably a small fraction of the greater structure's mass.  For reasons not at all clear, most of the optically radiant components of galaxies are arranged in a spiral disk, while others form the random elliptical orbit arrangements of elliptical galaxies.

Galaxies form - or are already created in - clusters of dozens to thousands of such greater galaxies.  The further reaches of their dark matter clouds, such as the 100 Mega K plasma aspect of the greater galaxy, merges somewhat with neighbouring galaxies and forms what we know as the Cluster IGM.

For the present hypothesis to explain how the vast, low-density, generally roughly spherical voids of Void IGM constrain heavy objects such as galaxy and galaxy clusters, some points as suggested below may need to be invoked.  Here I am considering the fluid dynamics and collision ballistics of stars and galaxies.

It may be that there is no way that anything can physically push a star (or a black hole, or quasar).  While hard objects such as black dwarfs can be pushed, stars cannot be, except perhaps very gently, by the very low density plasma of the interstellar medium.   It would be an interesting exercise in aerodynamics to calculate the drag of a star in the ISM!  However, over astronomical time scales, even moderate "wind resistance" of a star drifting against the ISM it is embedded in would probably appreciably affect the trajectory of the star.   At a first approximation, this would be true only if the excess pressure of the oncoming ISM in one direction resulted in increased pressure on the photospheric boundary (or whatever it is called where the outward accelerate pressure of whatever heats and drives the corona and stellar wind overcomes the star's gravity).  I would want to examine exactly what is occurring in the low corona, chromosphere and photosphere, once the coronal heating process has been reliably understood, before I could be confident that the simple idea of an ISM wind pushing a star was really valid.  For instance, if it could be shown that the force which pushes the corona away from the star is largely or entirely the momentum of the light which is absorbed / redshifted, rather than the adiabatic expansion of the plasma pushing back against the photosphere, then I am not convinced that an oncoming ISM wind would exert any physical force on the star.  To do so, it would have to cause the reflection of some light back to the surface of the star, where that light's momentum pushes the star.  Just having an oncoming ISM wind on one side of the star would probably not cause any appreciable force on the star if it simply absorbed and/or redshifted more light on that side.  If this is so - if stars are not pushed around by the ISM they are embedded in - then the spiral disk arrangement of stars in spiral galaxies is a function of gravity and the survival of stars which follow this pattern, since those which do not follow the pattern will be torn to pieces by tidal forces in the frequent collisions they have with other stars.  (I am flying a kite here - there's a lot more I want to think about.  At least, I hope this will stimulate thinking along fresh lines which leads to some better explanations.)

If the above is true, then gravity seems to be the primary, and perhaps only, determinant of a star's trajectory.  If all atomic or plasma material which comes near it is accelerated away by plasma redshift and/or Free Free Absorption (or at least whatever it is which drives the corona and solar wind) then it could be argued that it is impossible to push a star by means of anything like the very low density 440 Mega Kelvin Void IGM.  The only way that could occur is if the material of the Void IGM was streaming outwards from the centre of the void, and in some way dragging, or pushing, the star along with it.  But this assumes that the void IGM is, on average, moving.  It seems that the long-term structure of the voids and inter-void clusters is relatively static.  So if we assume there is no matter creation in the voids themselves, there we can tentatively conclude there is no net outflow of matter from the void to the clusters. 

Rather, it seems natural to suppose that the Void IGM is just like the Cluster IGM, but of a lower density due to it not being attracted to the mass of the greater galaxies and the mass of the Cluster IGM combined.   It seems natural to think of the Void IGM being like a higher temperature product of Void IGM "boiling" off the clusters and attaining a higher temperature due to its lower density and (as I understand it) its consequently lower capacity to rid itself of energy by Free Free Emission except by attaining such a higher temperature.

The bubble-like, or foam-like structure of the void - cluster nature of the Universe makes it natural to assume that the pressure in the voids is at least as high in their middle as on their boundaries with the clusters.  While the Cluster IGM in the middle of the clusters may be at a higher pressure, because it is at the centre of gravitationally bound cluster matter (Cluster IGM and galaxy dark matter - plasma, dust and black dwarfs), we naturally expect the pressure at the edge of the clusters to be identical to the pressure throughout the voids.

Since I can't envisage how the Void IGM could appreciably push a single star, or a galaxy full of stars if that's all there was to a galaxy, with the Cluster IGM acting against all the stars individually, I tentatively conclude that the Void IGM pushes against the Cluster IGM, which is approximately 1/4 the temperature and probably at least 4 times the density, and that the reason the galaxies remain embedded in this higher-density Cluster IGM plasma is because the major part of the mass of the entire cluster is in the Cluster IGM itself, rather than in the galaxies (including each galaxy's dark matter halo). 

To this conjecture, I would further speculate about the aerodynamics of black dwarfs and their fragments.  Here is a set of principles, including such mechanical coupling between the spherical halo ("dark matter") of black dwarfs and their fragments.

Radiant energy in the Universe is produced primarily by stars fusing light elements into heavier ones - and also by the gravitational collapse of material, primarily into black holes.  (Also, local heating and some radiant energy is created by gravitational collapse of gas and plasma into protostars, planets etc.)

This radiant energy, when passing through sufficiently low density plasma, is redshifted and so heats that plasma.

Lower density plasmas, on sufficiently large scales, are less able to get rid of this energy than higher density plasmas - because firstly they are not in physical proximity to anything colder, and secondly because low density plasmas tend to radiate less as they get hotter.

The resulting hierarchy of distribution of matter due to plasma pressure, aerodynamic drag and gravity is something like this:
The low density, very high temperature Void IGM creates roughly spherical voids, with everything else in the sheets and filaments (the superclusters) where the boundaries of these voids nearly touch.

The sheets and filaments are filled primarily (in terms of volume, but not necessarily by mass) with the Cluster IGM, which is denser and cooler than the Void IGM, but at about the same pressure.  The gravitational attraction of the galaxies in these sheets and filaments contributes to the higher density of this Cluster IGM compared to the Void IGM, which gives it a greater capacity to radiate energy, resulting in a lower temperature. (For this to be true, the increased density would have to result in a still greater increase in radiative ability, since for a given volume, the increased density also increases the energy deposition due to plasma redshift - but this last principle only holds as long as the interparticle distance still exceeds the coherence length of all relevant electromagnetic radiation.  Perhaps only the Void IGM is sufficiently low density that its particles are far enough apart to redshift the CMB . . . )

The black dwarfs are gravitationally bound, in general, to themselves in the dark matter spherical halos of optically visible galaxies.  (Are there dark matter "galaxies" with few visible stars in the current epoch?)

The black dwarfs are also bound, due to aerodynamic drag, to the Cluster IGM in which they are embedded.  They cannot collectively or individually attain (or maintain for long periods) high velocities with respect to this Cluster IGM.  So to the extent that the Void IGM corrals the Cluster IGM, it also corrals the black dwarfs, which constitute most of the mass of galaxies.

Visible stars are not so subject to aerodynamic drag in the Cluster IGM or Inter Stellar Medium - compared to black dwarf and black dwarf fragments.  However, they are gravitationally coupled to the collectively much greater mass of the black dwarf dark matter halo.

Stars, unlike black dwarfs, cannot survive close gravitational encounters, and so are generally not able to survive being flung into radically different orbits.  So those which survive as stars are those which move in a spiral disk, which itself is gravitationally guided primarily by the dark matter black dwarf halo it is embedded in.  (Elliptical galaxies are a clear exception to this general principle.)

Black holes are moderately coupled, by something resembling aerodynamic drag, to the plasma and other matter they move within.  This is not drag, as such, but the way a black hole acquires the mass and momentum of material it is travelling towards, much more than it does of whatever matter lies in its wake.   We naturally find black holes in the centre of galaxies, but perhaps they could be found outside galaxies due to a variety of circumstances.  These are discussed in the next section.

This is the best, or only, way I can account for the evident ability of bubbles of very low density Void IGM to push entire clusters of galaxies into a small subset of the available space.  In other words, the main mass of the clusters is non visible, and is in the form of 100 Mega K plasma, with potentially higher densities (and therefore lower temperatures, due to straightforward gas pressure considerations and also due to the greater ability of denser plasmas to radiate their energy as X-rays)  near the middle of the clusters, and in particular around the concentrated gravitational attraction of the greater galaxies.

In this view, visible galaxies are manifestations of a larger and heavier unseen body of dark matter - presumably mainly plasma at Mega Kelvin temperatures, plus, perhaps (as is my guess about the CMB) a graveyard of black dwarfs which probably significantly outnumbers the visible stars).  The visible galaxy stays within that greater body of black dwarfs (and their fragments) by that body's gravitation.

The galaxies stay in the clusters for two reasons.   Firstly they are attracted to other galaxies.  Secondly, the clusters remain constrained by the pressure exerted by the low density Void IGM, due to the Void IGMs much greater temperature - which itself is driven entirely by its own low density and the continual stream of starlight coursing though it.  (The emanations of AGNs and quasars contribute to the electromagnetic radiation which heats the Void IGM, via plasma redshift, but it is relatively minimal compared to the output of the stars.)

Galaxies, AGNs and Quasars

This series of hypotheses makes no claim about the origin of the matter, energy, structure, forces or dimensions of the observable Universe.  It attempts to provide simpler explanations for the observed redshifts - which if interpreted as Doppler lead to all sorts of contradictory conclusions regarding quasars and radio galaxies etc.  

First, let us consider black holes and where they may be found.  It is obvious from observations and theory that black holes are generally to be found in the centre of galaxies.  We could assume they are always formed there, or gravitate there after formation - after originating in gravitational collapse of neutron stars, supernova remnants, or a sufficient concentration of visible stars or black dwarfs.   However, perhaps they can also be formed with a high enough velocity to escape the galaxy in which they were created.  Perhaps (as Damien Miller suggested) black holes or their progenitor neutron stars could be created in asymmetrical supernova explosions, or in stellar collisions which resulted in high velocities for some of the remnants.

Ignoring the last point, and assuming that black holes naturally form only in the centre of galaxies, there may be one or more mechanisms by which the black hole could be ejected into a trajectory which removes it from the vicinity of galaxies.  This would lead to a population of "naked black holes" - which may be what we know as "quasars", since they are radiant, may have jets and lobes, and are feeding from the IGM, all without being in the middle of a galaxy. 

One way black holes could be ejected is if two galaxies collided, each containing a black hole at their centre (or actually anywhere inside them).  The galaxies themselves would be severely disrupted by the collision - both the visible and dark-matter components, due to tidal interactions with the other galaxy's mass (and to some extent the other galaxy's ISM) and also due to the influence of the other galaxy's black hole.  However, the black holes themselves would not be destroyed.  A black hole cannot be damaged or torn apart by tidal forces, no matter how close it gets to another black hole (but perhaps, if close enough, they could merge into one larger black hole). 

If two black holes came close enough they would interact primarily with each other's gravity, and the result could be that one or both of them are flung into trajectories totally different from those of the colliding galaxies, with sufficient velocity to escape both galaxy's centres of gravity.  Thus, one or both black holes could begin a long period of travel into the space, unencumbered by local attraction of masses of visible stars and black dwarfs.  The black holes may have little or no "aerodynamic drag" in the IGM, and so a population of them may be found traversing the Universe, on their own, independent, trajectories, distributed reasonably evenly in space, including in the Void IGM.  Their capacity to radiate energy depends on their surrounding plasma, and how fast they are travelling through it.  As noted above, they might be expected to concentrate plasma around them, giving a great deal more plasma redshift in their vicinity than would otherwise be the case in that distance of unconcentrated Void IGM, and so we would see them as point-source-like objects, with high redshifts compared to galaxies viewed through the same amount of Void IGM and Cluster IGM - and these black holes would potentially have radio-visible jets and lobes.  So we would observe them as "quasars" and "radio galaxies" - or as "BL Lac objects" if one of their jets pointed in our direction.

In my hypothesis, a quasar which is not embedded in a proper galaxy has a strong heating effect (via plasma redshift) on its immediately surrounding IGM.  This IGM is being continually gravitationally attracted, and eventually falls into the black hole, powering the quasar.  But this relatively concentrated (over parsecs or potentially thousands of parsecs or more) plasma has the effect of redshifting the optical emanations of the quasar far more per unit distance than the normal IGM.  Consequently, the observed optical emanations of quasars are highly redshifted, depending on their IGM environment, their mass etc. despite the quasars we observe on average being no more distant from us than the galaxies we observe.

An AGN is a galaxy with a radiating black hole (AKA "quasar") embedded in its centre.  This greater concentration of plasma around the quasar (compared to a quasar not in a galaxy) has the effect of producing less redshift around the quasar than would be the case if the same quasar, at the same distance from Earth, was simply embedded in the (collapsing) IGM.  (To-do - more thinking on this!)  I don't have an entirely clear idea of how this would occur - but it is a crucial principle to envisage if the hypothesis is to explain the observations.  Plasma redshift (if it follows the "dimple redshift" principle described above, or Ari Brynjolfsson's theory) is a curious phenomenon.  For a given wavelength - or more likely coherence length - it only really occurs if the plasma's inter-particle distance is greater.  But once the inter-particle distance exceeds this value, then the redshift per parsec (or any other unit of distance) is proportional to the plasma's density.

Thus, the quasar which is not embedded in a galaxy creates for itself a local concentration of the IGM which creates a great deal of redshift with various clouds of absorbing or emitting gas/plasma appearing in our observations at different redshifts according to how much of this redshifting plasma we see each cloud through.   Perhaps the quasar which is in a galaxy (such as a Seyfert galaxy) has such a high concentration of plasma around it that there is little plasma redshift, at least of the emission and absorption lines by which we perceive the galaxy and its black hole radiative core. 

So in this hypothesis, quasars in galaxies, such as Seyfert galaxies, do not have their light redshifted very much compared to the rest of the galaxy.  Therefore, we observe the redshift of these black holes and the stars in these galaxies just as we do for the stars in other galaxies - it is caused primarily by the light traversing through the IGM between the galaxy and us.

"Naked" quasars at the same distance and approximate location have their light redshifted by the IGM in the same way, but most of the observed redshift is caused by the local concentration of IGM they attract around themselves, perhaps whilst simultaneously pushing the plasma away to some extent with the momentum lost by their light being redshifted.

Correlation analysis of the combined galaxy and quasar catalogues from the 2dF surveys (2dFGRS and 2QZ) may support or reject the notion that high redshift quasars (and so-called radio galaxies, which as far as I can see, generally have no more evidence of a galaxy of stars than a quasar) are in the same places (clusters) as low redshift galaxies.   Or perhaps it can be shown that quasars are distributed in the skyplane in ways which do not match whatever clustering we might expect if they were physically located in the clusters of low-redshift galaxies.

The "Finger of God" effect

(Added 2008-11-03.)  See the Fingers-of-God and large voids in this image from SDSS: .

According to Google (2004 April 26), "Fingers of God" is used almost as much (284) with "redshift" as "finger of God" (309).

The mapping of galaxy distances from Earth according to their redshift shows some distinctive patterns of redshift dispersion, which I think are strongest only in directions where there are lots of galaxies.  It seems that where there is a dense cluster viewed end-on from Earth, a significant proportion of galaxies have an excessive (or at least, in the conventional view anomalous, both positive and negative) redshift compared to what we would expect.  Little or no such dispersion occurs in a linear cluster which runs at right angles to our line of sight.   This is conventionally explained by the observed redshift being caused not just by the expansion of the Universe, but also by local relative movements of galaxies with respect to each other.   If that were the case, then we would expect both positive and negative dispersions from what would otherwise be the normal redshift of the cluster - and in order to explain the relative lack of this scatter when viewing a filament of a cluster edge on, we would have to conclude that galaxy motions were generally along the length of the filament, rather than across it.  

This does not seem unreasonable, but if it can be shown that the redshift scatter largely positive, then this would not be explicable by the conventional theory, whereas it would be explicable by plasma redshift.  The always positive scatter would be caused by the greater density of IGM in the cluster contributing to a greater redshift in our line of sight, compared to that encountered by a similarly distant galaxy in an edge-viewed filament, in which the light travels primarily through the low, and apparently reasonably consistent density, Void IGM.

Some references with a redshift galaxy map from the CfA survey: Redshift-space Distortions, by Louis Desroches.  The CfA Redshift Survey.
(New material 2004 April 27.)

I have not attempted a full literature search on "fingers of God" and "redshift-space anomalies" - but if plasma redshift is responsible for most or all of the redshift which is conventionally regarded as Doppler resulting from the expansion of the Universe, then there should be plenty of evidence for this in the existing literature - though it may need to be re-interpreted somewhat to allow for a form of redshift the researchers had presumably not contemplated.

From John Huchra's site is the following image (copyright SAO - Smithsonian Astrophysical Observatory):
redshift anomalies fingers of god finger of god galaxy survey plasma redshift
A number of such "fingers" can easily be seen.  But compare this with a similar image at: which shows few, if any, such "fingers of god".  The fingers we see here seem to involve a redshift range of about 3,000 km s-1(if considered as Doppler shift), which corresponds to about  10-2 the speed of light.  From what little I know of this effect, which I think is something of an "embarassment" (observation which seems to challenge) to conventional theories, the effect is not seen so much on redshift plots with higher ranges of redshift.  If plasma redshift is the primary explanation for it, then this could be due to general limits on the dimensions of galaxy clusters, together with the redshifting rates of the IGM found in such clusters.

(Added 2008-11-03.)  However, if the fingers were purely caused by excessive redshift in denser IGM in clusters, then the fingers would only point out from those denser parts.  It is clear from the excellent SDSS image linked to above that the fingers point in too.  I guess this must be Doppler shift due to movement of galaxies.  The spread of velocities from the ends of the inwards tip to the end of the outwards tip seems to be 0.01 the speed of light.  Are galaxies really moving that fast?  I haven't done the math, but it seems rather fast for them to be oscillating back and forth being gravitationally bound to the other galaxies in the cluster - whilse still not breaking up due to tidal forces.  Are there measurement errors in this?  Are there just more fast-rotating galaxies in these dense parts of clusters with rotational rates which make redshift measurement more error prone.  

John Huchra's homepage also has an interesting historical graph showing estimates of the "Hubble Constant" from 1927 to about 2001. (To-do: consider other graphs and links on this page, including the detailed critique of distance estimates using Cepheid variables: .)

Two papers, which do not seem to be published or available via the Net:
Investigation of Possible Redshift-Space Artifacts in the Ursa Major Region via the Tully-Fisher Relation
E.A. Praton, M.J. Rothrock, Jr. (Franklin & Marshall Coll.), S.E. Schneider (UMass---Amherst)
We investigate possible redshift-space artifacts in the Ursa Major Group near the Virgo Cluster, by using the Tully-Fisher relation between spiral galaxy luminosity and rotation rate as a distance indicator. We use I-band magnitudes from Tully, et al. (1996), H-band magnitudes from the 2MASS database, and HI linewidths compiled from the literature. The slopes of our best-fit lines and the dispersion about the lines are compared to the recent Cepheid variable calibration of the I- and H-band Tully-Fisher relation (Sakai, et al. 2000). We look for evidence that galaxies in an Ursa Major structure, which looks like a finger-of-god redshift-space artifact, may in fact be in close physical association.

Rotational flows within superclusters? A comparison of redshift-space artifacts in the Local and Southern Superclusters
E.A. Praton, M.A. Berger (Franklin & Marshall College)

We continue a study of possible non-radial flows within the two nearest superclusters. Both the Ursa Major region in the Local Supercluster and the Dorado region in the Southern Supercluster show structures in redshift-space which look like the artifact expected for flow with non-zero curl about a small central cluster: a small finger of god, bisected by a ?bow-tie.?

Previously, we used the Tully-Fisher relation to confirm our identification of a finger in the Ursa Major region (Praton, Rothrock, & Schneider 2000). We now extend the investigation to include a comparison with the Dorado finger. We also use the T-F relation to investigate the apparent bow-tie artifacts in both regions.

E.A. Praton's homepage is .

Researching galaxy redshift scatter

(Added 2004-05-10, but see the 2008-11-03 addition above too.)

This section considers what appears, visually, to be reasonably symmetrical "fingers of God" redshift scatters in both negative and positive directions, at least looking at graphic representations of one of the CfA surveys.  I would need to do a histogram of the redshifts of such a cluster, together with thinking about the redshift of the cluster if it was not for the scatter (based on filaments it seems to be a part of) to decide this for sure.   If the redshift scatter could be shown to be entirely symmetrical, then this would be an argument against plasma redshift - since it is reasonable to expect plasma redshift to lead to more redshift per unit distance in the Intra-Cluster IGM than in the Void IGM.

The rest of this section doesn't specifically concern plasma redshift, so you might want to skip it and go to the next, which certainly does.

Using the 2dFGRS galaxy redshift data (see below #2dF ) it should be possible via one or more statistical analyses, to reliably distinguish between two theoretically predicted patterns of redshift scatter:
  1. Assuming standard Big Bang cosmology, the scatter is due to velocities of galaxies in galaxy clusters - so we expect the scatter to be symmetrical about the average redshift of the cluster.  Various types of analysis should be able to distinguish the most likely location of the skyplane and redshift location of the centre of the cluster, irrespective of the scatter, since the cluster is more likely to be aligned with less dense strings of clusters or galaxies which are at about the same redshift.

  2. If some, most or essentially all of the scatter is caused by plasma redshift in the denser IGM in the cluster, then the scatter will always be to increasing redshift.
I can think of various ways of analysing the data to determine this from the 2dFGRS and CfA data.  The observed scatter is likely to result from a combination of processes - and a positive scatter due to greater plasma redshift in cluster IGM could be hard to discern if it is relatively small compared to other processes, including:
  1. The genuine velocity movements relative do Earth as galaxies move in their (presumably random-like, since we don't see circular or spiral structures) orbits about the cluster's centre of mass. 
  2. Likewise genuine velocities as a few galaxies gain unusual amounts of velocity when they happen to swing by other galaxies - each encounter of which gives them a higher velocity.
  3. The errors of measuring the redshift of galaxies.  In a very dense area there will be more outliers due to measurement error alone and we would visually perceive these as "fingers of God".
  4. Any other, as yet unknown, mechanisms.
I tried to find better images of these "fingers", without much luck until I came across this magnificent animation :

Click the bottom "identify clusters" button loads an image which roughly labels the major galaxy superclusters.  Then click the top link "load movie (original data)".  This loads a bunch of .gif images which show the raw data of one of the versions of the CfA redshift survey (  Now click the "Play" link and be amazed!  I think its best to make it run a little faster than usual.  (By the way, the Javascript code for this seems to come from here.)  

This "original data" rotating image shows clearly the "fingers of God" effect - there are probably 20 such fingers clearly visible.

The "width" of the box is stated to be 230 Mega light years, so the "distance" from Earth at the centre to the left, right, top or bottom edge is 35.2 parsecs.  Since they convert to distance from redshift with the common 70 km s-1 megaparsec-1 Hubble "constant", this centre to edge distance really means a redshift of (expressed as velocity) 2469 km s-1- or more properly a redshift of 1.00823, where  redshift 1.0  corresponds to the centre.  The images are 298 pixels wide, so this means that 149 pixels corresponds to a redshift "velocity" of 2469 km s-1.  Therefore, each pixel away from centre corresponds to a redshift "velocity" of 16.57 km s-1.

I stopped the animation at a point where the longest "finger" in the bottom half of the image was probably pointing straight to the left: .  That finger points about 30 degrees down from horizontal.  The far end of it is out of the left of the image, but by visually judging its end when it is not pointing so far to the left or right, I estimate (using Photoshop's ruler) this finger reaches from about 60 pixels (994 km s-1) at its lowest redshift point out to about 215 pixels (3562 km s-1).  So the "finger", assuming it is one finger and not two in the same place in the skyplane but centred on different redshifts, covers a redshift velocity range of about 2568 km s-1.  This corresponds to a galaxy moving at half this velocity (1284 km s-1) relative to the cluster and still remaining part of the cluster due to the cluster's  gravity.  The standard interpretation of this redshift scatter is that it represents these velocities - that some galaxies in the cluster can be moving at such velocities (0.0043 the speed of light) and still be gravitationally bound.

Looking at another prominent finger in the same way leads to the velocity of a galaxy with respect to its cluster of  861 km s-1.  Other large fingers would lead to figures such as this and somewhat less.  (To-do: get the raw CfA data and analyse it to produce histograms for galaxy redshifts in these "fingers".)

A 1999 review paper:  The Early History of Dark Matter, by Sidney van den Bergh (Sidney Vandenberg):
gives a figure for the velocity dispersion in the Coma cluster of 1082 km s-1.

Let us compare this velocity with the escape velocity of the average galaxy. 
A few papers regarding rotation velocity curves and the dark matter halos required to explain them: 
The scatter of redshift in galaxies which are part of a cluster was recognised by Fritz Zwicky and Edwin Hubble in the 1930s.  A brief history of this is at: and a more detailed set of pages on the missing mass problem is by Robert S. Fritzius: .  There seem to be at least three primary angles on missing mass:
  1. Extra mass beyond those of visible stars in a spiral galaxy to account for their well-observed (via redshift and blueshift) orbital velocities - and how these can only be explained by assuming a large amount of invisible heavy material distributed in the vicinity of the visible galaxy.

  2. Invisible mass in galaxy clusters required (if Big Bang cosmology is assumed to be true) the ability of cluster galaxies to have a large velocity scatter, whilst still remaining gravitationally constrained in the cluster. (But then why doesn't the cluster attract nearby galaxies and clusters . . . ?)

  3. Mass invoked to explain the supposed large scale motion of matter in the Universe, assuming Big Bang cosmology is correct.

Towards a direct argument that the Fingers of God redshift scatter is too high to be the velocity of galaxies gravitationally bound in a cluster

The usual approach is to calculate the mass of galaxies, the density of galaxies in the cluster and then from the size of the cluster to figure out its gravitational potential and therefore its escape velocity.

I think there's a more direct way to challenge the notion that the redshift scatter is caused by movements of galaxies, assuming those velocities are due to the galaxies orbiting each other in a dense cluster.  This does not require the calculation of the dark matter component of each or any galaxy.  This line of argument does not seem to lead to convincing disproof of the standard interpretation.  But I think its interesting, so here it is.

Q1 What is the orbital velocity of stars in the average galaxy?

Looking at this review: velocities probably average 50 to 150 km s-1.

The paper
The extended rotation curve and the dark matter halo of M33
Corbelli, Edvige; Salucci, Paolo
MNRAS Volume 311, Issue 2, pp. 441-447
has rotational velocities for the M33 Triangulum galaxy (, which is close to our own (naked-eye visible), and apparently moving towards us at about 180 km s-1.  The orbital velocities are mainly 100 to 150 km s-1, rising slowly with increasing radius to the limit of the observations.

A survey of redshifts (reasonably used to determine orbital velocities) for the edge-on galaxy (its clearly a galaxy, and its not elliptical) UGC 9242 is at:  The velocities level out to about 230 km s-1 .

A site full of rotation curves - the rotational velocities of stars mapped against the radius from the centre of the galaxies: .  In particular, the image: shown here in a smaller form:

Velocity curves of galaxies

A1:  It is reasonable to assume that the rotational velocities of stars in galaxies are typically no more than 300 km s-1 and probably averages 200 km s-1.

Q2: What is the escape velocity of the average galaxy?

Escape velocity is 1.414 x orbital velocity (from an orbit around an object where all the mass is inside the orbit, which is not necessarily the case with galaxies at the radii shown above, but at least we can see that the orbital velocity doesn't keep increasing indefinitely) - so:

A2: It is reasonable to assume that the escape velocities of galaxies are typically no more than 430 km s-1 and averaging 283 km s-1.

Q3: What would be the escape velocity of two galaxies of equal mass and size, assuming for simplicity that they were spheres, if their edges were just touching?

Two equal mass objects receding with a given velocity is not like one such object and a very light one receding, since the "stationary" object tends to follow the "moving" one.  Another way of looking at it is that both behave like they are half the distance from  a single object of twice the mass.  Escape velocity is sqrt(2G x Mass / Distance), so if the distance X was 2 x the galaxies' radius, with the "edges of the galaxies" touching, this doubling of the mass and halving of the distance (we are now thinking of the distance and velocity of either galaxy to the centre-point between them) would lead to an escape velocity twice the normal velocity from the central point, which means that the galaxies would need to be moving 4 times their normal surface escape velocity in order to be able to escape each other's gravitational attraction.

A3: For an "average" galaxy this would be 283 x 4 = 1132 km s-1.  For galaxies with the highest escape velocity, this would be 430 x 4 - 1720 km s-1.

Q4: If galaxies were assumed to generally remain at least 10 radii apart, in order to avoid tidal forces, what would be the escape velocity of two galaxies this distance apart?

Instead of their centres of mass being 2 radii apart (edge-to-edge) the galaxies are now 5 times the distance.  Escape velocity scales with the square-root of distance, so the answers are 1/sqrt(5) = 0.447 times the abovementioned velocities.

A4: For "average" galaxies 506 km s-1 and for the larger galaxies  769 km s-1.

Q5: If the redshift scatter was interpreted as velocity, what would be the velocity range be, dividing the scatter by 2 to give the maximum velocity of a galaxy with respect to its cluster if this redshift really does represent velocity?

Looking at the CFA-Puck diagram above we can see various "fingers".  Assuming that the maximum redshift, when expressed as a velocity, is 15,000 km s-1 (maybe it is 15,000 km s-1) then the range of velocity for the "finger" at 16h is about 3,000 km s-1 .  Other "fingers" at about 1h, 5h and 7h are perhaps this size, but are at least 2000 km s-1. So this gives 1000 km s-1.

Looking at the animation discussed above I estimated 1284 km s-1 and 861 km s-1for the two most prominent fingers.  Other fingers would probably have values 900 to 600 km s-1.

The page states that velocity dispersion of rich clusters is 400-1400 km s-1 with a median of  ~ 750 km s-1.

A5: From 600 to 1200 km s-1.

Q6: How could a cluster of galaxies be in orbit around themselves (gravitationally mutually constrained) at velocities 600 to 1200 km s-1 which are generally higher than the escape velocity of a pair of reasonably spaced galaxies: 506 to 769 km s-1?

Maybe they could . . .   The question is whether a cluster of some hundreds or thousands of galaxies, with an average inter-galaxy spacing of some number of average galactic radii, such as 10 or so, could create a sufficiently strong and far-reaching gravitational field to cause such fast-moving galaxies to remain gravitationally bound. 

I assume that even the fastest galaxies do remain gravitationally bound, otherwise the cluster would lose galaxies and so become smaller - yet the cluster is evidently quite big.  For the purpose of this argument I also assume standard Big Bang cosmology that there is no force other than gravity restraining the galaxies - whereas my theory is that they are somehow corralled by the pressure of the Void IGM.

Let us imagine a cluster of 1000 galaxies where the average spacing is 10 galactic radii.  For simplicity let us think of each galaxy now becoming a sphere of 5 times its normal diameter, with its original mass, so we can make our cluster of such "fatter" galaxies all bunched together.  The new, fatter, galaxy has 5 times the radius of the original one, so the escape velocity, for a small object, is 1/sqrt(5) times its former value.  For the largest galaxies this is 430 x 0.447 = 192 km s-1 and for the average galaxies 283 x 0.447 = 127 km s-1.

It is now easy to estimate the escape velocity of a cluster of 1000 galaxies simply by imagining 1000 such "fattened" galaxies all bunched into a sphere.  The cluster diameter will be 10 times the diameter of the fattened galaxies and that its mass will be 1000 times greater.  This means that the radius from the centre of gravity at the edge of the cluster will be 10 times greater than before, which would mean the escape velocity becomes sqrt(10) of its former value.  But the mass would be 1000 times greater, so the escape velocity would scale by sqrt(1000).  Consequently, the final escape velocity, from the surface of this very dense cluster, would be sqrt(100) = 10 times the figures in boldface above.   (I used the "small object" escape velocity because a galaxy would be a small object compared to the cluster.)

But how realistic is this density, of galaxies being only 10 radii apart?

A reference is the first chapter of Formation of Structure in the Universe, ed. Avishai Dekel and Jeremiah P. Ostriker:

But I am running out of time . . .  (Clusters are not spheres - so there's lots more reading and thought to-do here.)

A6:  Maybe they could . . .  

Discerning plasma redshift due to local higher density of the Intra-Cluster IGM as a component of redshift scatter could be challenging, since there are major uncertainties about the dark matter problem - from the points of view of both galaxy movements in clusters (inferred from redshift scatter) and the missing mass needed to explain rotation velocities in galaxies.  Above I attempted to look at the feasibility of galaxy velocity dispersions based only on the escape velocities of galaxies - without trying to quantify the nature of the mass in each galaxy which gives these rotational and escape velocities.  It has been interesting, but it doesn't contain any significant support for plasma redshift or critique of the conventional theories. 

Ari Brynjolfsson's Plasma Redshift theory

Please see the start of this page for the URL of this paper.  Here is my understanding of some salient points.  But don't trust my interpretation - read the paper, which is linked to at the start of this page.  Be sure to read the appendices early on, rather than last.  I do not understand the mathematics of his redshift theory - and there is no other, more "tactile" or physical explanation. 

This theory provides for about 10-6 plasma redshift above the Sun.  It also provides for a magnetic heating process, of about the same strength.  The acceleration of particles in the solar wind, especially the preferential acceleration of heavier / more positive ions, is explained not by redshift, but by a diamagnetic effect.

The theory only predicts substantial redshift at high temperatures - say 200,000K or so.  (This is really oversimplifying it.  I am corresponding with Ari Brynjolfsson and he is giving me examples of the strength of the effect under various conditions.)  A stronger magnetic field will also increase the amount of redshift.

Ari Brynjolfsson states that his plasma redshift process accounts for the observed shift of Fraunhoffer lines, including their long-debated higher redshift at the limb.  Since there is no sign of gravitational redshift, which Brynjolfsson believes exists, he concludes that gravity must repel photons by the same degree as they are gravitationally redshifted.  This process is the subject of a forthcoming paper, but he explores the implications of such a process in the current paper.

He also discusses what most people refer to as black holes - stating that some, or all (I am not sure) of the infalling matter is converted into photons and radiated. 

I do not understand the mathematics of his theory at all - so I can't comment on it.  However, it does seem to be a different theory from my "Dimple plasma redshift" theory, such as it is - not least in that it works with electrons, while mine proposes that protons and other nuclei are important, perhaps dominant, participants as well as electrons.

It is great to have Ari Brynjolfsson's paper finally available, and to read his thoughts on the role plasma redshift plays in heating the IGM, and therefore (to my mind at least) affecting or controlling the large scale structure of the Universe.

While I think his theory and mine have some important things in common, please don't consider what I write on this page as necessarily applying to his theory at all. 

Thomas Smid's Plasma Redshift Theory

Thomas Smid has a theory based on the idea that short coherence length wavefronts are stretched by the electric field between the charged particles in low-density plasma: .  This was discussed in sci.astro.research in March 2006 "Plasma Theory of Galactic Redshifts and 'Gravitational Lensing' of Light".  See also the discussion around then: "Redshift of solar limb and in cosmology".  See also my Simmering page.

(Added to this page 2006-03-11.  I previously listed and earlier version in the "may be related" section below, as a "research proposal" in 2004 which was discussed on sci.astro.research on 2004-03-02:

Theories which may be related to plasma redshift

The late Paul Marmet's site has a redshift theory for atomic and molecular hydrogen.  See the papers: "A New Non-Doppler Redshift", "Redshift of Spectral lines in the Sun's Chromosphere" and "Non-Doppler Redshift of Some Galactic Objects".

There was an obscure paper in 1996 in the "Journal of New Energy" ( "A new approach to the cosmic red-shift and to the cosmic microwave sources" P. Anastasoviski, H. Fox and K. Shoulders (Volume 1 No. 2). This is reported to concern redshift and charged particles, but the paper is not on the Net or in a conventional journal, so I  haven't researched it further.  See also: .

Thomas Smid has a theory, which seems to involve plasma redshift

   . This was a "research proposal" in 2004 ( and was discussed on sci.astro.research on 2004-03-02:

The Quasar - Quasar Transverse Proximity Effect

2008-11-03: Significant updates regarding new observations of closely paired quasars.  

These updates will only make sense to people who already understand the predicted, but so-far unobserved, Transverse Proximity Effect.  The older, more introductory material, is below: #TPEorig.  This new diagram explains it:

Transverse proximity effect with a foreground quasar

In October 2008, thanks to Eric Lerner's Alternative Cosmology Group Newsletter I learned of a paper by David Kirkman and David Tytler , both of UCSD, on the Transverse Proximity Effect with a foreground quasar.  Their observations of 130 QSO pairs do not show signs of the Transverse Proximity Effect, as originally conceived and as searched for by previous Researchers, primarily Michael Schirber.  Prior to this study, which I will call "K&T", there were only a handful of attempts to find the effect, and none of them found it either.  Finding this effect would be an excellent validation of the BBT's redshift distance relation.  I think that repeated failures to find it is good evidence that the BBT is wrong.  The only apparent way of explaining the observations in a manner consistent with the BBT involves a number of propositions, which I think are unrealistic.  One of these is that QSOs only shine for a million years or so in any one burst of activity.  

The transverse proximity effect in the z ~ 2 Lyman-alpha forest suggests QSO episodic lifetimes of ~1 Myr
David Kirkman, David Tytler  2008-09-12 Submitted for publication in MNRAS

This uses 130 pairs of QSOs drawn from a larger sample in an earlier paper, I call "Tytler et al.":

Metal Absorption Systems in Spectra of Pairs of QSOs
David Tytler, Mark Gleed, Carl Melis, Angela Chapman, David Kirkman, Dan Lubin, Pascal Paschos, Tridivesh Jena, Arlin P.S. Crotts

In the K&T paper, the Researchers analyze their 130 close QSO pairs only by aggregating each foreground QSO's computed absorption.  Since there is a wide disparity of distances between the foreground QSO and the line of sight from the background QSO, I think it would be much better to analyze the 10 or so closest and most promising pairs, sorted by closeness or by the ratio of the foreground QSO's UV output to the UV Background level at the line of sight from the background QSO.   The closest are 0.1 Mpc from the LoS and the furthest are 3 Mpc. This is a 30:1 distance ratio with, on average, a 900:1 ratio in terms of how intense the UV is at the LoS. 

Ideally, I think, each of the pairs of QSOs should be analyzed individually.  Pair 1 is the closest, for which the Researchers use SDSS spectra. (See the next paper for more about this pair.)  For pairs 2 to 9 (I didn't check any more) are the Researchers use their own spectra, laboriously gained over (I guess) 8 or more years of research.  These spectra would be a great resource to other Researchers.  (2008-11-05: I understand that David Kirkman and David Tytler are still working with these spectra, so I imagine that the spectra would not be released until they have published all the research they want to do with them.)

In the table below, the distances (predicted by the BBT) between the foreground QSO and the LoS from the background QSO are here given in Mega light years, for the 9 pairs with the highest omega-max (the ratio of the foreground QSO's UV at the LoS compared to the UV Background level).  Pairs 1 to 9 in K&T's Table 1 happen to be the closest of the 130 pairs.

b Mly   omega-max      pair  (RW: Chance of NOT finding TPE
                              in ideal circumstances, with
                              1 million year active phases.)

0.32      2272.5        1     0.32
0.39      2715.3        2     0.39
0.45       123.1        3     0.45
0.58       149.7        4     0.58
0.68       119.5        5     0.68
0.71        62.4        6     0.71
0.74        25.1        7     0.74
0.81        33.0        8     0.81
0.88        53.8        9     0.88

Here are some files based on the table in K&T:
DK-DT-TPE-QSOs-raw.txt                    Table 1
DK-DT-TPE-QSOs-sort-b-LoS-separation.xls  Table 1 spreadsheet, with closest pairs first.
DK-DT-TPE-QSOs-sort-omegamax.xls          Table 1 spreadsheet, with brightest illumination of LoS first.

The Researchers  find no Transverse Proximity Effect.  They explain this in terms of:
  1. All QSOs having quite short active phases - such as 1 million years or so. (Yet their first 9 pairs involve distances from foreground quasar to line of sight from the background QSO of less than a million light years.)  The closest is predicted by the BBT redshift distance relation to be 0.32 million light years.
  2. All QSOs having a localised increased density of IGM, which balances out the ionizing effect of the UV they are emitting.
  3. This balance only occurs in these 1Myr active phases for parts of the Line of Sight (LoS) (from the background QSO) which are closer to Earth than the foreground QSO.  The light from the foreground QSO which ionizes the LoS further away from the foreground QSO doesn't arrive in time for us to see it partially ionizing this part of the LoS, assuming the active pulse and our observation is timed so we do observe the foreground QSO.
David Kirkman and David Tytler find a slight increase in absorption in the LoS at about the distance of the foreground QSO, and at greater distances.  This is the three bars in the middle of the lower part of Figure 4.  The right one is at the same distance as the foreground QSO.  The other two are away from the foreground QSO.  This roughly fits the above explanation.  However, this seems like a rather improbable explanation to me.

Firstly, why would the extra UV neatly balance out any extra IGM density?  Surely it wouldn't always do so.  If one balances the other sometimes, with some QSOs the extra density would dominate at any given radius and in others the foreground QSO's UV would dominate.  It would be unlikely for the two to balance, in any one QSO, for all distances.  

If their slightly raised absorption rearward of the foreground QSO is a real phenomenon, then surely they would be able to detect it more clearly with a carefully selected set of pairs - those where the foreground QSO is closest to the LoS.  I think their spectra would be a great resource to analyze - separately, in addition to their aggregated analysis.  

For instance, for pair 1, if the increased IGM density nicely counteracts the intense UV (up to 2272 times background levels) in the Earth-side part of the path which is illuminated by the active output phase which enables us to see the foreground QSO, then the part of the path further away from the foreground QSO should not be illuminated and we should see drastically increased absorption, due to whatever high density of IGM there is there, which was not illuminated in time for us to see this absorption reduced.

The shorter the phasic pulse which are assumed for all QSOs (300k years or less would be required to make the above simultaneous observations reasonably likely), and the longer the gap between phases, the more our observations of QSOs must under-estimate their true number.

The spectra of pair1, which the Researchers used, is available in SDSS. For pairs 2 to 9 (and many more) they use their own spectra.

I would like to do a proper critique of this, and of another significant paper:

Coincident, 100 kpc scale damped Ly? absorption towards a binary QSO: how large are galaxies at z ~ 3?
Ellison, Sara L.; Hennawi, Joseph F.; Martin, Crystal L.; Sommer-Larsen, Jesper

!!!! (2008-11-05)  The following critique - the text in grey, to the next set of red exclamation marks - is probably wrong.  Nonetheless, the diagrams of the spectra may be helpful in understanding the observations, including where in QSO B's spectrum the Transverse Proximity Effect is expected to be observable.

The spectrally wide nature of the absorption band in the Fig 2 section is not, as I assume below, a direct indication of its physical length along the line of sight from the B QSO.  It is primarily due to the high density of neutral hydrogen in a cloud which is not necessarily very long.  Neutral H atoms absorb not just at the precise 1215.87 Angstrom wavelength, but to a lesser degree at slightly shorter and longer wavelenths. This is not noticable when the concentration of neutral H atoms is low enough to cause only marginally noticable absorption at 1215.87 Angstrom, as is the case with the clouds which form the narrow absorption lines.  These are generally highly ionized, and only a small proportion of H is un-inonized, giving a column density (number of atoms, ions etc.) in a cm2 of  < 1017.2 .  (Imagine a block of space 1cm wide, 1cm high and L cm long.  It doesn't matter much whether the L length is a metre or a megaparsec, if this block of space contains 1017  neutral H atoms, this is the column density of this section of space in which the light travels along the L direction.)  See for a better explanation.

The absorber in the B part (bottom) of Fig 2 is estimated to involve a column density of neutral H atoms of 1019.85, as indicated by the "log N(HI) = 19.95".  The absorber in the A part (top) of  Fig 3 is estimated to have a column density 100.63 = 4.26 times greater, which gives a wider band of very high absorption, and wider "wings" - the curved sides of the absorption trough.

A denser cloud, which is not necessarily very long along the line of sight, could produce this absorption trough, so my critique about the cloud having to be very long (much longer than the separation between the lines of sight from the two QSOs) is probably invalid.

The Ellison et al. paper concerns two close quasars, the first pair in the Kirkman and Tytler (K&T) paper.  This is the closest pair of QSOs with spectra I know of.  In K&T, it is predicted (in the BBT framework) to involve the foreground QSO illuminating the line of sight from the background QSO to 2272 times the level of the UVB (UV background) radiation.  So this should be a pretty good test of the TPE.  AFAIK, the only publicly available spectra for these are from SDSS (please let me know if some others become available).  Ellison et al. obtained much better spectra with one of the Keck telescopes.  AFAIK, their spectra is not publicly available.  I think it would be a highly valuable resource to Researchers.

I did some rough work with the FITS files of the spectra used by K&T for this pair.  The spectra can be obtained from by setting this page to "Spectra (SpecObj)" and "plate-MJD-fiberID".  Then enter these two lines (aluminium plate for fibers, modified Julian date and fiber number):

1439 53003 595
1440 53084 238

Then click the button on the resulting page (upload list of spectra to DAS).  Each link opens a page from which a FITS spectra file of each QSO can be downloaded.  The 1439 file  is the A QSO in the Ellison et al. paper - the "foreground" QSO - the left one in the SDSS picture below.  The other is the B QSO, the slightly higher redshift QSO in the "background" (according to BBT redshift distances).  I was able to graph the spectra with SpecView ( ) but after a while, I found I couldn't get the program to produce images.   (Ideally I would do much better work than this, and use the Keck spectra.)

Ellison et al refer to these two QSOs as the QSO binary SDSS1116+4118 AB (SDSS 1116+4118 AB).  Here is the SDSS navigator picture:

This shows B in the centre and A to the left.  According to Ellison et al (late 2007), there is no spectroscopic redshift for the galaxy in the middle, although it apparently has a photometric redshift of 0.25.  In Google Sky: link

There is no mention of Transverse Proximity Effect in the Ellison paper.

Below is my rough graphic, showing part of QSO A's spectrum on the top.  This is mainly to the short wavelength end from both QSO's 1215.67 Angstrom peak emission - the Lyman-alpha forest of the two QSOs, although some of the lines are identified as belonging to other ions.  I have marked roughly in red where the QSO's 1215.67 Angstrom emission peaks would be, in the observed spectra, according to the emission redshifts estimated by Ellison et al.  I calculated 1215.67 x (1 + zem). 

QSO               RA          Dec         i mag Redshift (zem)  (RW) calculated observed
                                                                wavelength for 1215.67
                                                                emitted Lyman-alpha

SDSS 1116+4118 A  11 16 11.7  41 18 21.5  17.97 2.982+/-0.007   4840.8
SDSS 1116+4118 B  11 16 10.7  41 18 14.4  19.00 3.007+/-0.007   4871.2

The pink line from the calculated peak of A, the foreground QSO, descends to the spectrum of the background QSO.  That is where we expect (according to the BBT, but not to my plasma redshift model) to see a powerful Transverse Proximity Effect taking place - less absorption in this part of the observed spectrum due to the foreground QSO ionizing more (or all) of the neutral hydrogen in the part of the sightline from the background QSO where that Lyman-alpha absorption would have taken place.

There is no sign of such TPE, unless perhaps a little spike to the long wavelength (right) end of the pink line is it.  

With 70km/s/Mpc redshift, I think the BBT predicts that the foreground QSO is about 27 Mpc closer to Earth than the background QSO.  With this model, there is only about 110 kpc transverse distance from the foreground QSO to the LoS from the background QSO.

K&T predict the foreground QSOs UV emissions would exceed the UV background (UVB) at this ~110 kpc distance by a factor of 2272.  My rough calculation is that the foreground QSO's UV would still be at a significantly higher level than the UVB, such as 5 times as high, at a distance of (sqrt(2272 / 5) * 110) = 2.34 Mpc.  I figure that such a level of UV would show up as increased ionization of neutral H in that area, such that there would be less absorption and so a higher observed flux in this part of the spectrum, which I have labeled with a green bar, which extends to indicate the spectral location of Lyman-alpha absorption, in this observed spectrum of the background QSO, 2.34 Mpc on either side of the (BBT predicted) location of the foreground QSO.  This is rough calculation, so I may be wrong - actually, due to pixel restrictions, the bar is 1.7 times wider than this zone.

Lack of Transverse Proximity Effect with a foreground quasar in QSO binary SDSS 116+4118

Here is a detail of the right end:

BTW, these dips in flux in both spectra, short (to the left) of the emitted Lyman-alpha peak of the QSO (after redshifting to the observed wavelengths) constitutes the "Lyman-alpha forest".  (There are no trees in this forest - it is densely populated by absorption troughs.)  The clouds may be largely ionized, but if they have a small fraction of neutral H, they will absorb 1215.67 Angstrom light.

There's no sign of the Transverse Proximity Effect in this relatively coarse SDSS spectra.  This is a very close pair, the closest of K&T's 130 pairs.  

The "Fig 2/3/4" above refers to the parts of the observed spectra which are reproduced in these figures in Ellison et al.'s paper.  They propose that each of these three zones shows where a substantial neutral H cloud makes significant absorption troughs in one (Fig 2) or both (Figs 3 and 5) lines of sight from the two QSOs.  

The Researchers suggest that the cloud whose absorption is depicted in Fig 2 only substantially affects the background QSO's line of sight to Earth.

When I looked at the correlations between these two Lyman-alpha forests, I wondered whether perhaps the QSOs really were at their BBT redshift distances.  I thought about it very hard, because if they are, the BBT is true and I am wasting my time (and yours, Dear Reader) with all this plasma redshift stuff!

However, here is my rough critique of the BBT-compatible interpretation of the Researchers, followed by an attempt at showing why this observation would be easier to explain in a plasma redshift framework.  The Fig 3 and Fig 4 absorption troughs may well be compatible with BBT redshift distances.  Fig 4 looks the most likely to be compatible, with Fig 3 looking rather weak in absorption in the LoS from the background QSO.  

My critique concerns the Fig 2 absorption. Absorption is prominent in the LoS from the background QSO, but not evident above whatever else (small clouds, absorption by other absorbers than neutral H, at other redshifts?) is causing these absorption troughs in the corresponding part of the Lyman-alpha forest in the LoS from the foreground QSO.  The Researchers state this.

According to the BBT theory, the Researchers note that the lines of sight at this distance would be about 112 kpc apart.  (However, Fig2's absorption happens closer to Earth, further away from the QSOs than for Figs 3 and 4.  So why are the distances for Fig 3 and 4 less - 110 and 107 kpc respectively??)

The width of this Fig 2 absorption trough along the LoS from the background QSO can best be estimated by looking closely at Fig 2.  I estimate it is 3.8 Angstrom, according to the scale of Fig 2, in which the absorption trough is assumed to be (reasonably, I think) Lyman-alpha at 1215.67, in the absorbing cloud.  The graph is of the observed spectrum, but the wavelength scale is that of the light when it passed through the absorbing cloud.

Neutral H clouds are unlikely to be moving at great speeds relative to anything - unless they are part of the rotation of the edge of a galaxy.  They are not likely to have their atoms moving radically with respect to each other, since this would be heat and the collisions would ionize the atoms.

3.8 / 1215.67 = 0.00312 .  According to the BBT, the far end of the cloud was moving away from Earth at 0.00312 * 300,000 km/s = 938 km/s faster than near end. (I have never understood how, in the BBT, an object such as a cloud of H, which has some consistency as an object and which is presumably gravitationally attracted to itself, is nonetheless flying apart one end from the other, dutifully following the impetus imparted from the primordial explosion billions of years ago - though this is high redshift, so in the BBT, the Universe was a fraction of its present "13.7 billion years" age when the cloud was absorbing this light.)  

With 70 km/s redshift, the length of the cloud, along the LoS from the background quasar can be calculated: 938 / 70 = 13.4 Mpc.  Perhaps the BBT formulae predict a faster rate of expansion at the time when the light passed through the cloud.  Assuming not:

I undertand from this that the Researchers are proposing that there is a consistently absorbing cloud in one LoS which is 13.4 Mpc long, but is not causing comparable continuous absorption in the other LOS, which is about 0.112 Mpc away!  So the cloud has an edge which is straight to a degree of: 13.4 / 0.112 = 119!

I think this is impossible to imagine.  A 6:1 ratio between the length of the cloud and the distance to the line would be like this:

This is unlikely, but possible to imagine.  

Unless I am mistaken, the researchers are suggesting the absorption depicted in the bottom of Fig 2 is caused by cloud, about 20 times longer than that shown above - 119 times longer along the bottom LoS than the distance to the top LoS.

Even a long line of smaller clouds like this would be highly improbable, with most of them missing the other LoS - however, most of the absorption is so thorough in the second LoS, that I think it is best to think of a single cloud.

This idea of a cloud of enhanced neutral H having such a straight edge doesn't make physical sense to me.  Perhaps there is some other BBT-compatible explanation, but I can't think of one.

The observations could be explained in a plasma redshift theory, but please note I don't yet have a mechanism by which light is redshifted by sparse plasma.

There are several reasons for thinking it might be such a mechanism, which I will return to below.

In a plasma redshift model, the Lyman-alpha forest, and most of the redshift we observe in the light from a high-z QSO, is generated in a region of higher density IGM in the "vicinity" of the QSO itself.  I don't have a clear idea what this distance would be, but I guess it may be 100 to 1000 kpc or so.  I propose that the IGM in general - or rather the inter-cluster IGM - is all at about the same temperature and pressure, heated by whatever mechanism heats the solar corona, but in this case to a higher temperature due to the limited ability of the IGM to radiate its heat via brehmsstralung emission of X-rays.  The driving light is dim compared to the Sun at close proximity: ordinary intergalactic starlight (also perhaps the CMB?).  But it is pervasive and has been shining for a very long time - probably much longer than 13.7 billion years.  (I have no hypothesis on the origin of the Universe or whatever keeps galaxies going longer than current BBT-compatible theories say they should.)

For this explanation, I will assume most of the IGM is of a certain density which gives ~70km/s/Mpc redshift.  Closer to the QSO, I propose that the IGM is more dense over quite large distances.  I guess the gravitational attraction would be balanced to some degree by some repulsive effects, like the acceleration of the solar wind, but due to the light, UV, etc. emissions of the QSO.

The QSO may or may not be inside a "galaxy".  (Do stars form from the concentrated IGM as it is sucked into the accretion disc?  I guess they wouldn't last long.) My guess is that the highest redshift QSOs are not extraordinarily distant, but are black holes which have been ejected from galaxies, and are feeding on the IGM, concentrating it considerably into a region which produces a much greater redshift than 70 km/s/Mpc.

What happens to a black hole which is ejected from a galaxy?  What happens when a neutron star is ejected, as I think some are?  It would travel through the IGM, gathering mass as it attracts the IGM.  Eventually (we have arbittrary amounts of time to play with once the BBT is not assumed) these neutron stars would get heavier and heavier - until they became black holes.

Therefore, in a plasma redshift framework, when I look at the spectra of these two QSOs, I think the Lyman-alpha forest absorption lines didn't occur over vast distances and times, as the BBT predicts, but fairly rapidly, over much shorter distances, not far from the QSO.  Assuming there are some varying distribution of neutral H atoms in that concentrated IGM, then we will see the Lyman-alpha forest in the redshifted spectrum.

There is no direct way of telling how much of a QSO's redshift is due to its fast redshifting, locally concentrated, IGM and how much is due to passage through the general inter-cluster IGM at ~70km/s/Mpc.

My guess is that these two QSOs are behind the z~=0.25 galaxy - maybe twice that distance.  

Because there is considerable correlation between their two Lyman-alpha forests, particularly closer to the QSOs (closer - longer wavelengths leading to the redshifted 1215.67 Angstrom emission peak) my guess is that these two QSOs are close enough to largely share a single concentrated cloud of IGM.  In this way, both QSO's lines of sight pass through some clouds which are the same.  

The LoS separation at z~0.25 would be much less than the 0.1 Mpc calculated for z~=3.  So the zone of concentrated IGM might have a diameter of a few hundred kpc, with neutral H clouds big enough to sometimes cover both LoSes.

In this model, the high redshift QSOs are not as powerful as predicted with the prodigious distances implied by their BBT-based redshift distances.  Perhaps they are really at a distance of z=0.5, with the other 2.5 of their redshift being generated in their local zone of concentrated IGM.

There is still the potential critique about needing a long cloud to cover one LoS but not the other.  However, the problem is probably more tractable in a plasma redshift framework than in the BBT, because the longitudinal (along the LoS) distances for a given redshift, in this concentrated IGM, are much smaller than in the BBT.  The separation between the LoSes where the neutral H clouds are operating would be smaller too.

I don't want to make great claims about this, since there is still no actual mechanism for plasma redshift.  However I think this shows that these observations may be more easily explained in a plasma redshift framework than in the BBT.

!!!! (2008-11-05)  See the notes above at the first set of red exclamation marks.

Some reasons for thinking that there is a plasma redshift process.

This page already mentions the work of David G. Russell, who shows that certain kinds of galaxies have systematically higher redshifts.  This could be explained by these types having a more extensive coronae of plasma around them.  This page also mentions that since we don't understand the heating and acceleration of the solar corona and wind, we can't exclude the possibility that there is some currently unrecognized interaction between light and sparse plasma.  Perhaps one of those interactions will redshift the ripples of light as the run the gauntlet of speeding up to vacuum light speed, and being slowed down as they encounter each particle of the plasma, individually.  This slowing down involves momentum transfer to the particle, and I assume back to the light as it kicks off back into vacuum, before it gets close to another particle.

Another potential argument for plasma redshift is the "K-effect" - where certain classes of hot stars are found, on average, to have a positive redshift.  As far as I know, there is no contemporary explanation for this.  An account of this discovery, by E. B. Frost and J. C. Kapteyn appears in this biographical memoir by Otto Struve:

Halton Arp discussed it too in

This might be explained by these stars having a more substantial plasma corona, which redshifts their light sufficiently for us to observe it over the redshift caused by their movements.

Original Transverse Proximity Effect material.  This is what I wrote in 2004:

I will call this TPE - Transverse Proximity Effect - (2008-11-03, ooops!) rather than the less specific alternative name used by some researchers "Foreground Proximity Effect".  This is totally different from the "Proximity Effect" (AKA the "Foreground Proximity Effect") which is the absence of Lyman Alpha lines "close to" (in redshift terms, and therefore, implicitly, physically close to) the quasar.  The conventional theory of the quasar "Foreground Proximity Effect" is that no neutral H exists near the quasar, due to its high output of photo-ionizing light. (But why, then, is there a large emission line at this wavelength at or near the core?)   Both terms only have about 25 to 27 hits on Google in mid March 2004, and they point to a small number of papers, and one research proposal for the HST by an author of papers on this topic:  Gerard Williger ( "A test of the foreground proximity effect at z=1.2":

A test of the foreground proximity effect at z=1.2

The diffuse UV background flux J is a crucial component for
cosmological evolution models, though few determinations have been
made. The proximity effect, the thinning out of the Lyman alpha
forest near a sight- line's background quasar and explained at least
partly by the enhanced ionization from the quasar, is a key method to
measure J. A foreground proximity effect {FPE} should exist from
quasars close on the sky but at different z; it can constrain J and
test the enhanced ionization model. Galaxy clustering around the
quasar may modify the effect, but knowing the galaxy density around
the Lya forest should allow for corrections. We propose to measure the
FPE at z=1.2, which is advantageous because 1} the diffuse UV flux is
lower, and thus contrast with the UV flux of neighbouring quasars is
higher, and 2} galaxies are easier to identify at z=1.2. We have good
knowledge of the physical volume we wish to study through surveys for
quasars, MgII absorbers and galaxies, to constrain the
redshift-dependent galaxy density along the line of sight. We will
analyze the results based on pixel opacities, which is more sensitive
to fluctuations in J than traditional line counting, and will compare
our results with cosmological simulations to derive estimates of the
UV background in the context of available physical models."

Quasar spectra typically contain a series of absorption lines caused by Lyman Alpha absorption in neutral hydrogen atoms.  The light we see has been redshifted since this absorption at a single specific wavelength, and so we can use this as a probe of the multiple neutral H clouds along the line of sight as the light travelled from the quasar to us.

The Big Bang theory is that the redshift is caused by expansion of the universe - and that this expansion is pretty even over the entire Universe (not counting arguments that expansion is slowing down or accelerating).  Therefore, if the Big Bang theory is correct, these absorption lines can be reliably interpreted as a linear map of the line of sight, showing where each neutral H cloud is located.

This Lyman Alpha line - is about 0.1216 um (1216 Angstrom) and corresponds to the energy required to get the electron in an H atom from the lowest energy level to the one above, which is 13.6 electron volts.  This page has a good explanation:
Also: research/cosmology.htm

Added 2008-11-03: is good too.

Several sets of observations find evidence of TPE, up to a point at least, when a foreground galaxy is close to the line of sight.  Conventional theory is that the light from the galaxy will photo-ionize any neutral H in the vicinity, and therefore prevent there being any absorption in a range of the quasar spectrum which corresponds to that part of the line of sight.  (In my theory, this is fine, in general, although not every high redshift quasar is necessarily further from Earth than a lower redshift galaxy which is its neighbour on the sky plane.)

According to the Big Bang theory (the theory that all the observed redshift is Doppler, except perhaps a very small amount of gravitational redshift) the same should hold true of a quasar in the foreground: the quasar, like the galaxy, should photo-ionize a region of space, preventing the formation of neutral H clouds which, if they existed, would be observable as Lyman Alpha absorption lines in a particular portion of the spectrum of the distant quasar, which we view along a line of sight which supposedly goes very close to the foreground quasar.  High redshift quasars are (conventionally) believed to be more luminous than the average galaxy, so those who accept the Big Bang as fact expect the same effect (an absence of Lyman Alpha lines in an area of the distant quasar's spectrum corresponding to the distance of the foreground quasar) to be evident when a second quasar is close (according to its skyplane position, and its lower redshift) to the line or sight from a more distant quasar.   However, for all close pairs of quasars which have been investigated no such effect is observed.    This is most intriguing!

The best place to start reading about this is probably in Michael Schirber's thesis, section 8, page 160 (page 175 in the PDF):
Sources, Sinks and Scatterers of the Ultra-Violet Background
This refers to a paper he co-authored, which was submitted to the Astrophysical Journal in the middle of 2003, and which does not appear to have been published yet. (Note added 2004-05-12: this is now flagged as being approved for publication in the Astrophysical Journal.)  The thesis reviews the results of previous research on the TPE, with both galaxies and quasars as the foreground objects, and then discusses the three quasar pairs examined in the paper.  No TPE is found, except for some more distant (from the line of sight) quasars which are investigated by other researchers - and for one of the closer quasars, but not at the anticipated redshift.
The Transverse Proximity Effect: A Probe to the Environment, Anisotropy, and Megayear Variability of QSOs
Michael Schirber, Jordi Miralda-Escude, Patrick McDonald
(This paper was originally added to on 2003-07-21 and was revised on 2004-03-19.  The changes do not seem to alter the conclusions, and are primarily (in the version 2 page numbers) as follows. 3: Para deleted before "Several authors . . . " and new "Most often . . ."; 11-12: New para "One concern . . . "; 22: New para "Previous studies . . . " and changes to first sentence of next para.  On page 22 they discuss a reduction factor in foreground QSO, such as 0.07 of the expected flux, to account for their observations.  I don't understand the sentence: "The fact that . . . ".)

2008-11-03: Michael Schirber seems to no longer be involved in research, having now taken a second step towards to full ionization:

A somewhat later paper, also submitted to ApJ but yet to be approved, is by Rupert Croft (
Ionizing radiation fluctuations and large-scale structure in the Lyman-alpha forest
Rupert A.C. Croft

(Note added 2005-04-13:  See the discussion on sci.astro.research:
and a paper I should have linked to earlier, which claims to show an instance of the TPE with a foreground quasar, at a somewhat different redshift which places some constraints on the geometry and alignment of the quasar if all is as the BBT suggests.

Caught in the act: a helium-reionizing quasar near the line of sight to Q0302-003
P. Jakobsen, R. A. Jansen, S. Wagner, D. Reimers
Astron.Astrophys. 397 (2003) 891
Both Michael Schirber et al. and Rupert Croft find no evidence for the Transverse Proximity Effect from a foreground quasar.

A perfectly good explanation for this would be that the quasars are not at the distances these researchers assume them to be at (based on conventional Big Bang interpretation of their redshifts).  However, this possibility does not seem to have been contemplated in the above-mentioned papers.    Instead, the researchers put forward three potential explanations, all of which are unlikely and probably provably (as much as one reasonably can) wrong:
  1. The foreground quasar turns on and off, and it is visibly on for us now (after the billions of years its light has taken to reach us) but it was off a little time longer ago (a million years or so) so that it did not radiate at a time which would have affected the nearby line of sight when the photons we observed from the background quasar passed through that part of the line of sight.   There is no evidence for such turning on and off - to the contrary, many observations, especially of the large jets and lobes (although they probably aren't as big as generally believed, since the quasars are not really so far away) show that quasars (radio galaxies . . . whatever) remain "on" (radiating energy)  for very long periods.

  2. That the foreground quasar's energy is beamed towards us, but not sideways, so the line of sight to the background quasar in its vicinity receives less light than it would if the quasar radiated isotropically.

  3. That there is some kind of concentration of matter near the foreground quasar which shields the line of sight from the expected ionizing radiation.  (But if so, then how do we see the quasar, unless this cloud is anisotropic.)  This is one of the explanations being researched by Gerard Wiliger, as noted above.
(To-do: comment on Paul Martini's paper QSO Lifetimes, which makes specific comments on the TPE effect on page 9, and read and perhaps comment on "Why does Low-Luminosity AGN Fueling Remain an Unsolved Problem?":  )
The researchers debate the merits of these three explanations, but its clear that they are all highly unlikely, or at least at odds with reasonable interpretations of other observations.  The last point - about the foreground quasar not ionizing the line of sight to the distant quasar due to some kind of matter concentration which absorbs the ionizing radiation - may be subject to challenge based on the foreground quasar's own "proximity effect" - the lack of Lyman Alpha lines at redshifts close to that of the quasar, which are, in conventional "Big Bang: Doppler => distance" thinking, missing due to the quasar photoionizing the space around it.  If the spectrum of the foreground quasar has such a proximity effect, it should be straightforward in conventional thinking to calculate the radius from the quasar where this photoionization takes place (at least in the line of sight towards Earth) and then to argue that the same sort of photoionization should take place in all other directions, including to part of the line of sight to the background quasar. 

I believe these observations are a robust disproof of the theory (assumed to be true by these researchers, it seems) that quasar distances are directly and proportionally related to their redshifts.

Plasma redshift offers a straightforward explanation:

The bulk of the redshift of a high-redshift quasar is generated in a local area around it - a gravitationally condensed area of the IGM (or void medium).  (I also assume that these quasars are not imbedded in galaxies, which is contrary to the conventional thinking.)  Most of the Lyman Alpha lines are likewise generated by clouds of neutral H in these local regions - at least those absorption lines at redshifts approaching that of the quasar.  Ignoring the relatively small Doppler shift from proper motion (and there is no redshift from "Hubble flow" = expansion of the Universe) the rest of the redshift occurs in the longer distance through the very sparse IGM, on its way to us.

So when the line of sight to a quasar does appear to have its Lyman Alpha absorbing clouds ionized (or at least, prevented by some means from existing) in the vicinity of galaxies, we conclude that this part of the redshift was caused by the same, or similar, distribution of IGM through which we see the foreground galaxy, and that this IGM also has occasional concentrations of neutral H.

When TPE is not observed with a pair of quasars, it is simply because the quasars are not as far away as the researchers think they are.  With plasma redshift providing most or all of the observed redshift, there is no reason why the high redshift quasar of the pair should be further away then the low redshift quasar.  It might be, but it might not.  Only a fraction of the observed redshift is caused by the IGM and the actual distance through IGM to the quasar vicinity.  The rest of the redshift (not counting a little Doppler caused by the quasar's real movement and by movement of the various clouds of plasma/gas which generate the emission and absorption lines) is generated in a zone of more concentrated ITM plasma relatively near to the quasar. 

I predict that such pairs of quasars will show some correlation of any Lyman Alpha lines closer (in redshift) to Earth, but zero correlation for those which formed closest to the quasars, because those absorption lines "near" each quasar are formed in each quasar's own zone of denser IGM.

This absence of TPE seems to have been thoroughly established.  I regard it as an excellent disproof of the Big Bang theory.

This may seem a bit fast and furious, so let us consider this step-by-step:
The observations of (at least in some cases) TPE with a foreground galaxy show that the expectation of TPE is realistic, if we accept that the redshift of the foreground object is not intrinsic - that it is caused by whatever (typically, not counting finger of god effects and other anomalies which may go unreported) causes the cosmological redshift observed for galaxies of various apparent distances.

The failure to observe it with a foreground quasar shows that the foreground quasar's redshift is caused to a large extent by something intrinsic to the quasar and the space immediately surrounding it.  If all the redshift of quasars was caused by the same, generally predictable (as per the 72 km per second per Megaparsec Hubble "constant"), then (assuming the lines of sight are straight, which is a  reasonable assumption) then we would see TPE with a foreground quasar.

It is reasonable to assume that the last part of the redshift, as the light travels most of the distance towards us from the foreground quasar, takes place by the same mechanism as it does with galaxies.  (According to the Big Bang, this is entirely due to the Doppler effect caused by the expansion of the Universe.)  Therefore, we can proceed on the basis that the first part of the redshift, starting from the quasar, occurs in a small region of space surrounding the quasar.  ("Small" relative to the distance between Earth and the quasar.)

(It is fairly natural, in this setting, to assume that high redshift quasars are located, on average, very broadly speaking, at about the same distances from Earth as low redshift galaxies, but for now we need not make that assumption.)

There is no clear division in features in the spectrum of a quasar between the "last part" which seems to follow the pattern of low redshift galaxies (and at least which is shown to occur in space in the same way, as shown by the existence of TPE with a foreground galaxy) and the "first part" which is "intrinsic" to the quasar and its nearby space.  Therefore, it is reasonable to proceed on the basis that the quasar somehow concentrates the redshift process close to itself - that there is a single redshift process, which is generally at the Hubble rate in open space (for instance the Void IGM or intracluster IGM), and rises to a much higher level in the vicinity of quasars, but not Seyfert galaxies.

That being the case, then unless we invoke some bizarre time-warp process in the vicinity of the quasar, we must conclude that the single redshift process is not Doppler caused by the expansion of the Universe.   Gravitational redshift in the high values needed to explain quasar redshift has been ruled on on theoretical grounds in the past, and this seems reasonable.

Therefore, we are left with the redshift process being something which happens in space, without the need for movement of the distant object with respect to us - and which happens at one general rate in "ordinary" intergalactic space, and at much higher rates near quasars.

There are possible theories other than the plasma of the IGM being responsible for the redshift, but they would probably involve exotic notions such as quasars emitting fluxes of neutrinos or more obscure particles which somehow cause the redshift.

The most obvious explanation is that light is redshifted by passage through low-density plasmas, and that the Void IGM is a very low density plasma, which explains most of the observed redshift of most galaxies.   However, if we view galaxies (or anything else, including quasars) through a large enough distance of higher density Intra Cluster IGM, then the light undergoes a considerably higher redshift than would occur if the entire line of sight was in the Void IGM.  Here is a potential explanation for the gathering of a higher density of IGM (but still low enough to redshift the light, and perhaps microwaves we observe) in the immediate vicinity of a typical high redshift quasar: the quasar is a small object, just a black hole, without a galaxy, and for high redshift quasars at least, it has been in the Void IGM or Cluster IGM for so long that it has gravitationally concentrated that IGM a great deal in its immediate vicinity, as it feeds on this material to generate its light and other forms of electromagnetic radiation.

The exact nature of the neutral hydrogen clouds which cause the Lyman Alpha forest is not immediately obvious.  Perhaps they are areas of the IGM which are cool enough, or subject to some other factors (such as dust and/or heavy elements to cool it, and or allow the temporary formation of hydrogen atoms, even in a very low density) sufficient to create enough neutral H to create the absorption lines.  It seems that some of these clouds extend into space well away from the concentrated local IGM around the quasar - otherwise we would not be able to observe the TPE with a foreground galaxy. (Actually, it could be argued that the foreground galaxy itself may be in a localised concentration of IGM, complete with a few neutral H clouds, and that the line of sight from the background quasar passed through this local concentration.)

We have some reliable notion of the potential size of jets and lobes - from the VLBI observations of jets and lobes created by the AGN core of a galaxy which can be observed in detail optically.  Since we have a reasonable estimate of the galaxy's distance, from both redshift and from its angular size, we can develop broad estimates of actual sizes of jets and lobes of those quasars we regard as "radio galaxies".   Then, based on the reasonable assumption that a BL Lac object is our observation of a jet and lobe pointing towards us, obscuring the quasar core) we can look at how rare Lyman Alpha forest lines are in the spectra of BL Lac objects (as I understand it - otherwise it would be easier to derive a redshift for these objects), compared to the spectra of quasars.   Then, on the basis that majority of quasar Lyman Alpha forest lines are generated in the concentrated IGM in its immediate vicinity, we can estimate that a large proportion of this redshift happens at a radius less than the radial distance from a quasar to its lobe.  In other words, the statistics of the relative lack of Lyman Alpha forest lines in BL Lac objects, taken together with the reasonably assumed statistics of the radius of the lobes of quasars from the "quasar" itself (where it exists in a galaxy we can be confident of the size of), enable us to estimate how close to high redshift quasars most of their redshift occurs.  (Actually, there could be a very wide range of sizes of jets and lobes, from small ones in the denser confines of a galaxy, to very large ones beyond the main matter of a galaxy, or very large ones in the Void IGM, so the above suggestion is surely simplistic.)

The plasma redshift theory (or multiple such theories) enables us to propose that the quasar's absorption line region is very close to the quasar, compared to how far it is calculated to be according to the standard Big Bang theory.  This explains why quasars generally have such absorption lines, whereas with the Big Bang theory, they are supposed to be so far from the quasar itself, that it is difficult to understand how a quasar could maintain such a structure, especially when it is considered that (according to the Big Bang theory) they must be drifting apart - and therefore that the entire absorption line system is a spherical shell around the quasar, expanding with the expansion of the Universe, which is counter intuitive with a quasar which feeds by attracting matter towards it.

If, as I expect, the first and largest part of the redshift of high redshift quasars will be shown to result from plasma redshift (or something vaguely similar) in the vicinity of the quasar, then this, on its own, means that the Big Bang theory would have to be entirely revised.  The Big Bang theory has grown into a complex network of interlocking theories and formulae, in which many observations are considered and a series of supposedly self-consistent constants and cosmological parameters are calculated.  Showing that quasars are local objects, probably mixed up with galaxies, or at least at similar distances and maybe existing in the voids, would require a complete revision of all the Big Bang theories and calculations.

But I feel certain that the plasma redshift explanation of quasars' intrinsic redshift will also explain some or all of the observed redshift of galaxies, and furthermore a lot of the "finger of god" effect.  In that case, there's no reason to believe the Universe is expanding at anything like the rate currently widely believed, so the Big Bang theory has to be either completely abandoned, or recast on a vastly longer timescale, along with theories about how the Universe could be relatively static.  In order to do this, a number of things will need to be explained:
  1. The bubble-like large scale structure of the optically observable galaxies.
  2. The heating of the Void IGM, as well as the Intra Cluster IGM, and the coronae which seem to surround galaxies.
  3. The heating of the solar and stellar coronae, and the acceleration of their solar / stellar winds.
  4. The nature of the Cosmic Microwave Background, and the other background radiations, in the X-ray and gamma-ray regions of the spectrum.
  5. Olber's paradox - why the sky is generally dark.
We will probably have to admit that we have not a clue about the origin of the Universe - its matter, energy, forces and dimensions (including time). 

Science requires that we do not claim to understand things that we don't.  I think is unlikely that humans will ever be able to perform scientific observations which give concrete evidence about the origin of the matter and energy which make up the aspects of the Universe we observe.  It is impossible for me to imagine how we could make observations about the origins of the forces (electromagnetism at least, and maybe gravity - also maybe the strong and weak nuclear forces, and whatever forces explain things such as ESP, which Western science generally ignores), the three dimensions and time.  Any scientific theory and observations about the origin and nature of time and the three dimensions must be in made in entirely different terms, which I believe will be beyond our capacity to imagine, or at least to scientifically evaluate.   Anyway, we will never scientifically know the answer to the ultimate question: "Why is there anything, at all, anywhere?".

Coronal / Solar Wind Element Fractionation: the FIP Effect

Perhaps plasma redshift plays a role in the fractionation of elements in the chromosphere - where some elements are apparently ionized and then lifted upwards in preference to others, and above a certain altitude, all atoms and ions are swept upwards into the transition region, and then to the corona and solar wind.  I propose an explanation for the higher level of FIP fractionation in the slow solar wind, as part of my suggestion that plasma redshift is the mechanism by which ions are lifted preferentially.

The section following this one contains proposals for testing for plasma redshift in the lab, or at least for approximately replicating the conditions in the cooler part of the chromosphere and using concentrated sunlight to see if light will selectively move a low concentration of ions in an otherwise atomic low density gas.

In the following discussion I have ignored helium.  According to a paper:
Hydrogen and helium in the solar chromosphere: a background model for fractionation (of low-FIP elements)
Hardi Peter and Eckart Marsch
Astron. Astrophys. 333, 1069?1081 (1998)
Helium fractionation does not seem to occur in the upper chomosphere, where low-FIP elements are believed to be fractionated.  From page 1080:
"The main result of this subsection is that the ionizationdiffusion processes leading to the fractionation, i. e. the FIPeffect, of the minor species cannot work similarly in the case of  helium.

. . .

For the minor elements the fractionation processes are located in an ionizationdiffusion layer in the chromosphere (Marsch et al. 1995, Peter 1996). But in the case of helium no significant change of its abundance can be found in such a thin layer. The conclusion from this is that the abundance variation must be explained by a large-scale coronal/solar wind model, like the one of Hansteen et al. (1997)."
I haven't read this paper fully yet, and the discussion below does not concern helium.  Perhaps the above quote indicates that the researchers expected there to be a single zone (such as a particular altitude, temperature range or part of the magnetic and flow structure) of the chromosphere where fractionation took place, and that all elements which were ionized in that zone would be lifted higher in preference to neutral atoms - and that it seems that whatever fractionates helium could not be working in the same zone as is theorised to fractionate the low-FIP elements.  Perhaps, with more understanding of this field, I might be able to develop a more comprehensive theory of fractionation, which did not involve a particular zone of lifting ions, but in which ions were preferentially lifted at any location where the conditions for plasma redshift were satisfied.  But devising and modelling any theory in this field is daunting, even if the chromosphere material flowed and diffused in simple flows all over the Sun, without the various currents of material in magnetic regions etc.  which surely play an important role. 

Also, if it could be shown that a helium atom slowed light more than a hydrogen atom (which would not be surprising considering its greater mass), then a "plasma-redshift-like" process could occur, if helium atoms were sufficiently spaced amongst hydrogen atoms.  Then, the wavefront would travel at one speed in the effectively homogenous hydrogen and be slowed by the individual helium atoms - provided they were far enough apart.  This does not involve plasma - my "dimple redshift" theory really applies to any situation like this where particles, molecules or grains of dust present isolated "obstacles" to wavefronts of electromagnetic energy.  Therefore, perhaps the process could operate with pure water with just a few Na and Cl ions. (I wonder what would happen if, in an homogenous medium of a particular refractive index, a particle, molecule etc. created a small area with a lower refractive index.  Perhaps tiny bubbles in a liquid would be an experimental model.)

(To-do: The introduction of the above paper mentions high-FIP fractionation factors of 10 or so for polar plumes.  I haven't looked at this yet. There are other papers by Hardi Peter I want to read too.  A paper is cited: "Widing K.G., Feldman U., 1992, ApJ 453, 987" ... why don't astrophysics paper references include the title???  This reference seems incorrect.  There are many papers on solar abundances etc. in AdsAbs by Widing and Feldman.)

(To-do: read the various pages at: .  This concerns the fractionation of elements, and isotopes.  It would be neat if the differing masses of each isotope affected their plasma redshift to a degree which also affected their fractionation.)

First, some background information (based on my understanding of currently accepted theories) and references:

The solar wind is a largely collisionless extension of the corona - and extends radially in all directions to distances such as 20 or more AU without significant interference from outside the solar system.  There are streams of particles from outside which pass through, and to some extent interact with, the wind, but these are not the subject of the following discussion.

The solar wind is known, broadly, to exist in two distinct forms: "slow" and "fast".  "Slow" solar wind travels around 300 to 400 km/sec and is reliably known to originate in parts of the corona which themselves originate in active areas of the photosphere.  These active areas are equatorial, and vary with the solar cycle.  "Fast" solar wind is typically 500 to 900 km/sec, and originates either from the polar coronal holes, or from coronal holes which are located closer to the equator.  The majority of the solar wind, when measured over all angles from the Sun, originates in the polar coronal holes.  Solar wind detected in Earth orbit and other locations in the ecliptic may come from this polar coronal hole "fast" source, or from slower "fast" streams driven by non polar coronal holes - or it may be "slow" wind from an active area.  This "slow" wind is also called "interstream".

The "fast" wind from equatorial coronal holes is generally slower than that from the polar coronal holes - with the slowest speeds arising from the smaller equatorial holes.  There may be some other differences between the two types of "fast" wind, such as in elemental abundances or charge state, but these are relatively minor, and the two types of "fast" wind are clearly in principle the same, compared to the "slow" wind.

The slow wind has differing proton fluxes and elemental abundances from the fast wind.  There are also typically differences in charge state for ions between the two types of wind.  Since the heavier elements (astronomers call anything other than hydrogen and helium a "metal") may exist with a range of numbers of electrons missing, analysis, such as by the Ulysses spacecraft, can show systematic differences in the proportion of ions of each element which are in particular states of ionization.

There are also differences in velocity, and "temperature" of the wind in general (protons, alpha particles and electrons) and in the individual heavier elements.  "Thermal" velocity is the statistics of the velocity of individual particles which differs from the average bulk motion of such particles, or of some other reference set of particles.  These "thermal" motions can have all sorts of odd ("non-Maxwellian") distributions in three dimensions, such as a general distribution of most particles having random velocities in all dimensions, with a certain percentage of them having much higher velocities in one particular direction.

It is an outstanding problem of astrophysics to understand the origin of these two types of wind - though many aspects of the question now seem to have been reliably resolved.  The above account (as far as I know), along with many other details of how the wind travels in waves, spiral arms or whatever as it leaves the Sun, are well established and seem beyond reasonable doubt.   However several key questions remain, and when these are resolved properly, will lead to a greater understanding of the corona, the transition region and the chromosphere in particular.

One question is why certain elements are more abundant in the slow and fast solar wind than they are believed to be in the photosphere. (The photospheric abundances have to be estimated from spectroscopy and other techniques, while the solar wind particles can be captured and counted.)  The elements which are more abundant are the "low FIP" elements - those whose First Ionization Potential is lower than about 10 electron volts.   Another question is why this preference for low FIP elements is both stronger and more variable (on timescales such as hours to weeks, as far as I  know) in the slow solar wind compared to the fast.

Broadly speaking, it is generally agreed that in or near the chromosphere, low FIP elements are ionized and preferentially transported to the transition region and corona over those which are low FIP elements.  There is debate about whether this is a process of concentrating the low FIP elements or depleting the high FIP elements, but I don't concern myself with this, since that depends on what "reference" one uses for whatever it is considered is transported upwards without bias.

A good presentation on First Ionization Potential is by P J. Brucat: though the energies listed there are in ergs rather than the electron volts preferred by astrophysicists.

Most current theories of fractionation involve magnetism in either the elevation of the ionized elements and/or their confinement in flux tubes while they are elevated by some other means, whilst neutral atoms escape the flux tubes.  My theory does not require an magnetic structures or forces - other than sunlight, which is of course magnetic.

There are several views about how the preferred elements become ionized.  The usual view is that their ionization is primarily or solely a function of the temperature at certain levels of the chromosphere, since the higher the energy required to strip an electron of an atom, the higher a thermal temperature will be required to achieve this en-masse.  Another view, often combined with the first one, is that UV and EUV radiation coming down from the chromosphere plays a role in the ionisation.  This is particularly intriguing, since it is reasonable to assume that photons of energy greater than about 10 eV will not pass far in those parts of the chromosphere which contain a lot of neutral hydrogen, due to the Lyman Alpha absorption of such photons.  This ties in nicely with the observed cutoff of elements which are preferentially found in the corona and solar wind - those with FIPs below about 10 volts.

I have not seen any suggestion that these low FIP ions may be ionized, in part at least, by photons arising from the photosphere, though I guess that there must be some small flux of sufficiently energetic photons in the black-body radiation of the photosphere.  (Perhaps the Planck curve falls off so rapidly that this can be ignored - but the photosphere is very close and bright, and perhaps there might be effects of temperature and lower energy photons which do lead to some ionization.)

One theory from Hardi Peter, which I will discuss more fully below, is that very low FIP elements such as Ca are partially or wholly ionized in the photosphere, and survive in an ionized state as they are lifted up through the minimum temperature zone (historically known as the "reversing layers", I believe) and remain at least partially ionized when they arrive at higher parts of the chromosphere where it is reasonable to expect fractionation to occur.  This may no longer be an active theory of his, but I think it is worth bearing in mind.  I have not considered what the timescales are - based on diffusion, turbulence (as must exist to stop the chromosphere stratifying gravitationally with the heavier elements at the bottom) and the general upwards transport of material towards the corona.

I don't clearly understand many of the various fractionation theories, so I can't properly summarise or critique them.  However, I think it is fair to say that they generally involve the following themes:
The fact of an atom being ionized, at a particular level in the chromosphere, causes it to be preferentially lifted (compared to neutral atoms of the same element and of other elements) to a higher level in the chromosphere, or into the transition region.  Above that, whatever the mix of elements is, this body of material will be transported to the corona, and subsequently to the solar wind.  

While there might be some selective processes regarding the solar wind composition as it arises from the corona, these are generally regarded as being non-existent or of far less importance than the fractionation which is believed to occur in the upper chromosphere. 

Some or most theories have the ion being preferentially elevated (or at least held in a generally vertical flux tube, in preference to neutral atoms) because it is ionized.  However, perhaps some theories (I don't think I found one) suggest that the ionization process (such as by absorbing an EUV photon coming down from the corona) gives the ion sufficient thermal energy to gain altitude.  (This assumes that there is some kind of hydrostatic equilibrium, with less pressure as the altitude increases, but maybe it is more complex than that with the material reaching the transition region and virtually exploding, and of course with various turbulences and systematic patterns of upward and downward movement.)

Many theories propose some kind of fractionation process involving a time-sensitive tussle between ionisation time and diffusion time - but I find these theories hard to understand.

While the effect is generally called the "FIP" effect, some theories focus on First Ionization Time as a better predictor of the way different elements are fractionated.  In this view, as far as I know, the First Ionization Time is a function of the FIP of each element, and the specific fluxes and wavelengths of EUV radiation at specific locations in the chromosphere.  The idea is that those elements which in these circumstances are ionized quickly are those which are preferentially found in the corona and wind.   One intriguing aspect of this theory (I am not sure if I read the following, or made it up myself) is that there could be marked differences in general in the downwards EUV between active (slow wind originating) and quiescent (I think this, and "quiet sun" means polar or equatorial coronal hole) areas of the Sun.   In particular, the higher and more variable EUV radiation we expect to find in active area may be argued to play a role in the stronger and more variable fractionation of low FIP elements in the slow solar wind.
Generally, with these theories as I understand them, it is not clear to me exactly why ions would be preferentially elevated over neutral atoms of the same and other elements.   As I describe below, I believe plasma redshift could provide such a mechanism, even though the chromosphere is primarily neutral - and irrespective of any special magnetic arrangements.

This discussion is about the Sun, but the principles of any successful theory must also be applicable to what is known about element fractionation on stars of various kinds.  The situation of two types of wind, with particular elemental abundances, is likely to be specific to the Sun and similar stars, with stellar observations indicating that different kinds of stars have radically different, including opposite, types of elemental abundance differences between their photospheres and coronae.

One place to start is an article in 1989 by R. von Steiger and J. Geiss (who first wrote about the FIP effect in 1982):
Supply of fractionated gases to the corona. von Steiger, R.; Geiss, J.; Astronomy and Astrophysics, vol. 225, no. 1, Nov. 1989, p. 222-238.

A comprehensive roundup of observations, especially from Ulysses, in 2000 is:
Composition of quasi-stationary solar wind flows from Ulysses/Solar Wind Ion Composition Spectrometer.

von Steiger, R. ; Schwadron, N. A. ; Fisk, L. A. ; Geiss, J. ; Gloeckler, G. ; Hefti, S. ; Wilken, B. ; Wimmer-Schweingruber, R. F. ; Zurbuchen, T. H. 2000  J. Geophys. Res. Vol. 105 , No. A12 , p. 27,217 (1999JA000358)  << The preprint
I think this as essential reading!

This summarises the key observational findings about fractionation and the speed and variability of the two types of wind.  As far as I know, this is all still valid and widely accepted.  It corrects previous impressions that the fast solar wind had little or no fractionation, and has new figures for the fractionation, which are lower for both fast and slow winds than before, due to a revised photospheric abundance of oxygen, against which abundances are often measured.

The slow wind is found to exhibit low FIP element fractionation with a factor of 2.4 and for the fast wind, 1.8 - with the reference being the sum of the high FIP elements. (Table 2 page 8 of the preprint.)  Plate 4 contains the key results for the slow and fast winds.  There is a detailed and graphic discussion of the different patterns of charge-states of various ions and what this can be used to infer about the state of the corona from which the wind arose.

In the discussion section is a summation of the requirements any models must meet in order to explain observations:
"1. There exists a bias of low-FIP elements relative to photospheric abundances in both the fast and slow solar wind.

2. The low-FIP bias in the slow solar wind is stronger by about a factor of 2 than in the fast solar.

3. The variability of elemental abundances is stronger in the slow solar wind than in the fast solar wind. For example, the 1-sigma variability for Fe in the slow solar wind exceeds 40% for the period closest to solar minimum ("Min") while it is less than 20% in fast solar wind streams (compare Table 1).

4. The charge state distributions for all species are very different in fast and slow solar wind. For carbon and oxygen, charge states in fast and slow solar wind may be used to easily characterize a freezing-in temperature, formed at the point when the solar wind convection time becomes smaller than the ionization and recombination times. The oxygen freezing-in temperature is
1.1MK in the fast solar wind and about 1.6MK in the slow solar wind. [Freezing-in means the temperature of the corona where the wind apparently was formed and left to become the largely collisionless stream we observe at 1AU and beyond.]

5. The charge states of elements heavier than oxygen and carbon cannot be easily characterized by a single freezing-in temperature in slow solar wind.

Taken together, these observations show that the sources and elemental fractionation processes are fundamentally different in fast and slow solar wind. The charge states also constrain acceleration models of the solar wind [Ko et al., 1997]. Indeed, models of elemental fraction and models of solar wind acceleration must contend with these observations."

Then follows an interesting discussion of some theories of fractionation and wind formation.  In one, "wave heating on large coronal loops" is invoked to explain ionized atoms having a larger scale height.  (Scale height is the height at which pressure drops by 1/e.)  I think this is a way of saying that the ions are heated so as to collectively exist at a higher temperature, and therefore partial gas pressure, which would in an "ordinary" atmosphere in hydrostatic equilibrium, if the temperature was not lost through collisions, increase the height at which the ions would soon be found.

Two interesting papers are from Peter Wurz.  Firstly his thesis from 1999:
Heavy Ions in the Solar Wind: Results from SOHO/CELIAS/MTOF
This has the first substantial observations for calcium abundances in the slow and fast solar winds (although the fast is from a moderate speed equatorial hole, I think, rather than from a polar hole as was the case for the Ulysses observations described in the previously mentioned paper).  Calcium is rather low on the FIP scale - lower than previously observed elements.  These first observations with an uncalibrated detector showed Ca being enriched at a higher level than normal for a low FIP element, in both the slow and fast winds (Fig 3-3).  The fast wind Ca abundance was particularly high, and lead the author to develop and interesting theory to explain it.  A later paper, listed below, in 2003, made after the author and co-workers calibrated the space-borne detector by testing and identical device in a purpose-built facility, has entirely revised results for calcium, which place its levels just where they would be expected on the basis of other low FIP elements. 

While this first, tentative, result about Ca turned out to be spurious, the paper is interesting for its theory and for the figures it reproduces from two papers by M. Arnaud and co-workers in 1985 and 1992.  These figures are below:

(Fig 4-4) Ion fraction for selected elements, considering only ionization by the electron gas at a certain temperature in the solar atmosphere and assuming ionization equilibrium, according to Arnaud and co-workers.

Neutralization rates of selected singly ionised species in solar chromosphere
(Fig 4-5) Neutralization rates from singly ionized species as derived according to Arnaud and co-workers.

Wurz develops a theory to explain Calcium's enrichment, based on a fractionating process which I don't clearly understand, but which elevates all ionized species into the transition region.  As I understand his thesis, he suggests that Ca may be ionized in the photosphere, due to its low FIP, and rise to the "fractionating region" (presumably in the higher chromosphere) via the cooler region of the chromosphere, whilst still remaining ionized, due to its low recombination rate.

While this theory is not mentioned in the paper (below) which gives the revised Ca enrichment figures, I like this approach of considering novel ways by which the atoms of particular elements might be ionized.

The next paper has the revised Ca figures:
The Calcium Abundance in the Solar Wind
P. Wurz, P. Bochsler, J.A. Paquette, and F.M. Ipavich. Astrophys. Jou, 583 (2003), 489-495

Fast and slow wind velocities

Here is a theory which I think is currently considered to be plausible, in my own words rather than a quote from wherever I read it - but perhaps some of it is of my own creation, though that doesn't mean that such things have not been suggested previously.

The high speed nature of the wind arising from the polar and equatorial coronal holes is due to it being accelerated away from the Sun (by what?) along generally parallel, open, lines of magnetic flux.  Thus, it encounters no magnetic or other barriers, and the accelerative force works on the plasma for a longer time, and starting closer to the Sun, than for the wind which arises from active regions.  The fast wind, I imagine, arises as part of a continual transport upwards (not counting various dynamic motions, such as may affect a fraction of the material - spicules are often cited as such, but I don't think they are as dramatic as others do) of matter from the top of the chromosphere, through the transition region and corona, and then out to form the fast solar wind.

The slow solar wind originates in areas in which magnetic loops and the like abound to quite a large distance into the corona.  The wind material is theorised, by others (and it seems reasonable to me) to be generally stored in these active structures - so when it is released, it begins its acceleration outwards from a higher altitude.  If it is imagined that the accelerative force is generally proportional to time spent in bright sunlight (that is, close to the Sun) then it can easily be imagined that the slow wind is slower due to starting its acceleration from a point of lower irradiance.

Conventional theories have sunlight playing no role in heating or acceleration of the solar wind (although there is often references in the general astrophysical literature to "radiative acceleration", which must, I guess, in conventional theories, result from scattering and absorption rather than a redshift process).  However, once the plasma reaches a sufficiently low enough density (large enough interparticle spacing) my plasma redshift theory (such as it is) predicts heating and acceleration per second in direct proportion to the brightness of the sunlight.  (Actually, close to the disc, where sunlight is coming from the sides as much as from below, arguably there is more heating due to the particles receiving momentum from the left, right, front and back, as well as from below.)  Ari Brynjolfsson's theory probably makes similar predictions, but (as I understand it) the temperature of the plasma needs to be above about 200,000 K, and magnetic fields enhance the process.

So if plasma redshift does accelerate and heat particles in the upper chromosphere, transition region, corona and solar wind, then the two different starting points for the two types of wind may provide a simple explanation for their differing speeds.

Fractionation of low FIP elements - does plasma redshift play a role?

The exact details of the sun's atmosphere will remain elusive for a long while yet.  Here is a simple hypothesis of fractionation which may serve as a starting point for further thought.

I assume that any material which reaches the base of the transition region - the top of the chromosphere - never returns to a lower value, and is rapidly heated and accelerated upwards.   Simply looking at the density and temperature curves in the big NASA diagram above makes it easy to see that the pressure (which is not shown - we must imagine it by multiplying the temperature and the density . . . though we also need to remember that the pressure would approximately double, assuming a constant volume, when the atoms become ionized into protons and electrons, since this doubles the number of particles in the parcel of material) does not vary as dramatically as the declining density, due to the huge increase in temperature.  But the decreasing density means that the upwards velocity must grow very rapidly, in order to transport enough material upwards to feed the corona's constant generation of the solar wind.  (Somewhere I have a  paper with modelled velocities, which when considered properly, reveal accelerations of about 1000 G at one point.)

For now, I will nominate the base of the transition region, which is the top of the chromosphere - as the "boiling off point".

On this basis, fractionation for the corona and solar wind abundances must involve the preferential transport of some elements rather than others to this "boiling off point" compared to their abundances at the base of the chromosphere.

The mass of each atom of the various elements seems to play little or no role in coronal or solar wind abundances, so we must conclude that the chromosphere is generally so turbulent (and/or subject to some other mixing processes) as to mechanically mix all atomic and ionic species so as to maintain an approximately photospheric set of abundances, unless some other mechanism intervenes.  In the absence of this mixing process, gravity would intervene and make it difficult for any element other than hydrogen to rise to the transition region and corona, so we reasonably assume sufficient mechanical mixing due to turbulence.  (Apparently thermal diffusion can't support the observed mixing over the required heights.)

Here is my hypothesis, for a simplified atmosphere of neutral hydrogen (FIP 13.6 eV), with small concentrations of Fe (FIP 7.87 eV) and Ne (FIP 21.56 eV).  There may well be other reasons for preferential lifting of ionized atoms - but perhaps plasma redshift plays an important or dominant role.
Suppose none of the three species are ionized at the temperature minimum point in the chromosphere, say 400 km altitude above the photosphere.

As the mixture rises (probably very slowly since it is still dense compared to the corona) it reaches an altitude, or set of conditions including a certain density, temperature and level of irradiation (from the black-body UV of the photosphere, plus - probably crucially - whatever EUV has filtered down through the hydrogen above from the corona) that some of the Fe atoms become singly ionized.  Let us call this altitude or set of conditions (it could occur at various altitudes depending on local pressures, vertical mass flows etc.) the Fe First Ionization Level.  Using the NASA diagram above, and the "Fig 4-4" above (from Peter Wurz' dissertation), for the purposes of this discussion, I nominate the temperature to be 5,200 K and the altitude 1,200 km.

Due to the low abundance of Fe atoms in the material, and the small fraction which is ionized, the average distance between Fe ions will be larger than the average coherence length of sunlight.  (Let us say this length is 5 microns and the average distance exceeds this - such as 10 microns.)

Then, if several things are true, I believe that there could be a plasma redshift effect on this Fe ions, despite them being embedded in a sea of neutral H, Fe and Ne atoms:
  1. There is a plasma redshift process, as described above, which does not depend on either magnetic fields or any particular temperature for the plasma.

  2. The individual contributions to refractive index (slowing light) made by the three neutral species (H, Fe and Ne) are all about the same.  (Otherwise, plasma redshift would work, to some extent, on isolated neutral atoms of minority elements, if that atom had a higher "refractive index" than the surrounding atoms - resulting in fractionation irrespective of ionisation state.)

  3. The refractive index of a singly ionized Fe plasma is significantly higher than the same density of neutral Fe atoms.  (This is conjecture, but I figure that a singly charged atom will have a stronger interaction with a passing wavefront of electromagnetic radiation than a neutral atom would.)

Then, it could be argued, that each of the sparsely distributed Fe ions would slow the wavefront in its vicinity to a slower rate than it travels in the intervening material: neutral H, Fe and Ne.   If that is the case, then this is the same as plasma redshift in a suitably low density plasma, and I would expect the Fe ions to receive energy and momentum in same way as for plasma redshift, as they individually redshift each wavefront to a very small degree.

That energy would heat the Fe ions - which may well contribute to them rising higher, assuming the chromosphere is in some kind of hydrostatic equilibrium (but if that's the case, then why don't all the heavy elements settle to the bottom of the chromosphere?)  My crude theory predicts plasma redshift occurring in rough proportion to the charge of the particle multiplied by its mass.  The Fe ion is the only particle with a charge in this part of the chromosphere, and it is much heavier than the most common atom in the vicinity: H.

The energy deposition is accompanied by momentum deposition in the direction of the light's travel - so each Fe ion is pushed away from the Sun.

Thus, the elevation of any ionized atom might be explicable by plasma redshift, in addition to potentially several other processes which achieve the same result.

Note that this process has no role for magnetic confinement.  However, the solar atmosphere is not a simple system of ever-rising layers.  The exact manner in which various mixtures of elements are transported up and down, exposed to EUV and various temperatures, and then given time to be preferentially lifted towards the "boiling off point" is sure to be complex and beyond our ability to fully understand at present.

Different rates of FIP fractionation for different elements

In the above example several factors affect the final degree to which Fe is preferentially fractionated into the corona:
  1. The altitude of the "boiling off point" (in this example defined to be the top of the chromosphere).

  2. The relationship between altitude and proportion of Fe which is ionized.  This process starts at, in this example, 1,200 km - and the ionization fraction would grow at higher altitudes as the temperature and exposure to EUV increased.  (Also, arguably, as more free electrons and Fe and other ions circulate, the rate of ionization might increase further still.)

  3. The thermal diffusion of Fe ions, compared to Fe and other neutral atoms between 1,200 km and the "boiling off point".

  4. The way neutral gas was elevated.  (Over the whole Sun, a function of density and the total flow required to replenish the corona, but likely to vary greatly according to local conditions.)

  5. The effect of plasma redshift heating and momentum, against the forces of diffusion and "friction" (if we can think of ions having difficulty moving at speed through this tenuous gas) - so resulting in a degree of upwards drift for Fe ions from the time they are ionized to the time where they reach the "boiling off" point.

For the same overall conditions, a number of things may affect how each element is or is not fractionated:
  1. Its FIP - and so the relationship between altitude and fraction of the atoms which are ionized.

  2. The propensity of photospheric UV to photoionize the atom.

  3. The propensity of chromospheric EUV to photoionize the atom - and the flux and spectra of this will change markedly at different levels in the chromosphere.

  4. Differences between the elements in how they flow in the gas - or higher in the chromosphere, in the increasingly complete plasma -  according to the upwards accelerating forces, such as plasma redshift, and/or increased scale height due to the ions' higher temperature.

As others have suggested, perhaps what is happening in the upper reaches of the chromosphere is that H is being progressively ionized as the material moves (generally) upwards.  The combination of increasing, or relatively static temperature as the altitude increases, combined with an increasing amount of coronal EUV (as there is less and less neutral H to absorb it) leads to a steady growth in H ionization, as the density also drops several decades.

At some point, at the top of the chromosphere, and surely at or below the altitude at which the material "catches fire" (I suspect largely due to the interparticle spacing reaching the distance where plasma redshift becomes effective for the protons in the plasma) there is a point of no-return - the "boiling off point" - at which the elemental abundances of the corona and solar wind are fixed.

If the elevation of low FIP elements is wholly, or largely, a function of the plasma redshift process, which I described as taking place in relatively high density neutral H, then this redshift and preferential lifting process arguably stops working once the Fe ions are surrounded by a significant number of protons, which I assume will slow the light considerably more than the neutral H atoms, or if the Fe ions become so densely spaced that the interparticle distance is too close to support the redshift process.  If so, then the preferential acceleration may not be so strong near the top of the chromosphere.  It is less important there anyway, since the material on average, is travelling upwards at a faster rate, and has less time to go before crossing the "boiling off point".

Considering the number of variables which even this quick exploration suggests, and assuming that some process like this occurs, it seems a remarkable thing (and therefore a challenge to this theory) that the low FIP elements are enriched by amounts which are so similar between the elements. 

Different fractionation factors for slow and fast winds

Assuming that some process such as the above occurs, I will hypothesise on why there is a greater fractionation of low FIP elements in the slow solar wind.

The fast solar wind comes from quiet sun areas - polar and equatorial coronal holes.  In these areas, magnetic lines are open and vertical.  As argued above, whatever accelerates the gas/plasma upwards finds no resistance in this regime.  (It is a problem for many conventional theories that this lack of magnetic complexity is associated with the most efficient acceleration - since conventional theories rely on magnetic complexities to deposit energies into the plasma.)

Therefore, I would argue that the time the material spends between the low FIP elements being ionized and the bulk of the (progressively more and more low-FIP-enhanced) mixture reaching the "boiling off point" is significantly lower than in polar and equatorial coronal holes than in the active areas.  This hypothesis depends on some points I discuss fully below.  But if this argument is accepted for the moment, it can be argued that the quiet sun is a stable, fast-track, launching place for the corona and solar wind compared to the active regions - so it makes sense that there is little time for low-FIP enrichment, that the resulting corona and wind characteristics are stable, and that the wind velocity is high.

For this to be the case, we need to argue for some characteristics of the active regions which explains the differences in the wind characteristics.  The first one is obvious - the variability of fractionation is due to the complex and time-varying nature of the conditions in the active regions, from the photosphere and well into the corona, compared to those in the polar and equatorial coronal holes.

The lower speed of the active region wind has already been mentioned - it seems reasonable to attribute it to the wind's starting point being in the low to middle corona, rather than the photosphere as it is in the polar and equatorial coronal holes.  (Differing charge states of the various ions are easily explained in much the same way - the wind has a higher starting point and shorter history as a continuous stream when it arises from an active region.)

The final principle to explain is why more low-FIP fractionation occurs in active regions.  Here is an attempt - and there may well be multiple reasons, given the complexity of the active regions and the multiple paths material may take on its journey to the corona and wind.
For one or more reasons, the time the material spends in an active region between low-FIP element ionization and reaching the "boiling-off-point" is longer than in polar or equatorial coronal holes.  This could be caused by one or more factors:
  1. For a variety of reasons, on various scales, the more complex, intense and closed nature of the magnetic structures in active regions creates something of a barrier to the outward flow of material through the corona.   So the forces which elevate both the general chromospheric mixture and low-FIP element ions are not working into a relative vacuum as they are in polar or equatorial coronal holes.  Instead, in an active region, at the altitude (or perhaps rather the time of travel from the photosphere) at which we would normally find the "boiling off point" in the coronal hole area, we may find that the upwards motions are slower, being confined by a higher pressure of material above, due to restrictions caused by magnetic structures.  Consequently, the material spends more time (and probably more distance, but perhaps less distance, due to the compression from above caused by the constrictive fields) being elevated before it reaches the "boiling off point" - the point where the acceleration process finally overcomes gravity and other restrictions from above, and blasts the mixture away from the Sun at such speeds that there can be no more fractionation of elements.

  2. In an active region, the generally higher level of EUV from the corona may lower the altitude at which low-FIP elements first become ionized - and so generally increase both the time and quantity of these atoms which are subject to preferential elevation.

  3. In an active region, greater turbulence and various structures at lower levels of the chromosphere may increase the transport of previously fractionated material from high in the chromosphere down to lower regions, where it spends more time still being fractionated.  In other words, the straightforward process of the polar and equatorial coronal holes is replaced by one in which some proportion of the fractionated material is held back from escaping through the "boiling off point" and so is subjected to longer periods of preferential elevation of ionized elements.

  4. Perhaps, due to upwards and downwards currents in the photosphere and low chromosphere, some low-FIP elements which are ionized in the photosphere are elevated into the chromosphere to the point where the preferential elevation process (such as the plasma redshift one I described above, but also potentially other processes) works on them - so low FIP elements do not have to wait for thermal + EUV ionization in order to be preferentially fractionated.  This is easy to imagine with various dramatic events such as flares, magnetic loops etc.

Some of these ideas are specific to a plasma-redshift effect in isolated ions in an otherwise neutral chromosphere - but others may be generally applicable to other fractionating processes.  While plasma redshift may not turn out to be exactly what I envisage it to be, I hope that researchers will take a greater interest in sunlight in the various unsolved problems in solar astrophysics!   I don't accept that the textbook view of light and matter is entirely adequate - because this view apparently fails to provide a basis for a full explanation of several phenomena which have been studied intensively for decades.

Laboratory tests of plasma redshift and the role of light in low-FIP fractionation

Here are some ideas for testing astrophysical processes on Earth.  These would make handsome experiments for grad students!  If I get the time and a bit of money, I will be tempted to try the second one myself.

Ari Brynjolfsson, in his paper (page 50) proposes tests of plasma redshift such as observing the redshift of stars whose light passes through the low corona, as observed during an eclipse.  But he writes that he has failed to conceive of reliable and practical laboratory tests for his theory.  Part of the reason for this is the inherent difficulty of detecting necessarily very slight redshifts in light which necessarily is highly incoherent and so has a broad spectral nature (in order to create photons with a short coherence length, in order to be less than the interparticle distance of the plasma being tested).  Another reason, for his theory at least, is its dependence on high temperatures, such as 200,000 K or so.  

However, he does propose an extended version of the Pound Rebka experiment, with low-density helium in a much longer vertical tube between source and detector.  (The Pound-Rebka experiment has not, to my knowledge, been replicated - but it concerns the absolutely crucial question of general relativistic redshift of photons travelling up or down a gravitational field. )  His proposal does not seem to involve heating the helium to a high temperature.

My plasma redshift theory, such as it is, does not require the plasma be at any particular temperature.  I hold no hope of detecting redshift as such in any experiment on Earth, for the reasons of small redshift with incoherent light just mentioned.  However, perhaps it would be possible to detect the effect of light on the plasma, by its heating of the plasma and/or the momentum it couples to it.   By carefully varying the conditions, it should be possible to show that such effects occur in accordance with a plasma redshift theory, rather than by already known mechanisms such as free-free absorption or various types of scattering.

Sunlight is free and easily concentrated with a large mirror or lens.  The required interparticle spacings can be achieved with Earthly high-vacuum equipment, though it would be a challenge.  Perhaps if a focussed beam of sunlight was shone into a plasma in a tube, then the momentum coupling could be detected by a higher pressure (more likely a greater count in some ion detector) at one end of the pipe.   Any such effect could be characterised according to the interparticle spacing of the plasma, the spectrum of the light (via the use of colour filters before the mirror or lens) and by chopping the light on and off quickly whilst seeking correlated ion pressure readings, in a way which lowers the noise-floor of the experiment, and tends to isolate the results from other effects of the light such as heating of the container walls.

There is a potentially easier test of plasma redshift's role in the fractionation of low-FIP elements in the chromosphere.

I propose an apparatus with a small central glass tube (say 3cm wide and 10cm long), along which focussed sunlight is shone left to right.  To the right and left of the tube are larger volumes of enclosed space, with entry and exit windows for the light which will not be troubled by the focussed sunlight - so they may be a few tens of centimetres from the central tube.  (This means bigger windows - I am thinking of two oscilloscope tubes, with their phosphor removed, each joined where their electron guns normally reside to form the central 3cm wide tube.)

Then it is a matter of filling the apparatus with mainly hydrogen, and a small amount of one species of gas, such as Calcium (perhaps injected or ablated from a solid piece via an electron beam or laser . . . ) and for instance, Neon.  The pressure required to simulate the mid chromosphere should be achievable without exotic vacuum equipment, getters etc.   Then, there needs to be a way of ionizing some of the Ca (or whatever element is chosen as the ion to be fractionated).  This could be by heating the gas (with microwaves or electrical discharge - but we don't want to ionize the hydrogen) or probably best by exposing the gas to light which will ionize the Ca, but not the H or Ne.   Then there needs to be two sensitive detectors of Ca concentration - one for the left lobe and one for the right lobe of the apparatus.  If the conditions are right, and there is a plasma-redshift effect as described above in the section on element fractionation in the chromosphere, then we expect the light to preferentially accelerate the Ca ions to the right.  So we expect to detect a greater concentration of Ca in the right lobe, and less in the left.   Perhaps a pair of mass spectrometers could be used to detect Ca levels, though this sounds like overkill.   Perhaps the Ca or whatever could be radioactively labelled and counted with Geiger counters next to each lobe.   Perhaps there are chemical capture methods of assaying the relative concentrations of Ca in each lobe.

Any such effect could be explored by finding its limits and behaviour with light of various colours (affecting the energy of each photon, but filtering also increases the coherency, and so requires particles more widely spaced than plain unfiltered sunlight), and especially by finding a concentration of ions  above which the effect diminishes and disappears. 

Even if there was no plasma redshift, this experiment would explore the potential (and currently ignored, it seems) role which strong sunlight may play in the preferential elevation of low-FIP elements into the corona and solar wind.

If you got this far and found it even vaguely interesting then please write to me, irrespective of how credible you think it is: .

The remainder of this page has links to other resources and an update history.

Astronomy and Astrophysics Resources and Links

Websites - reference and search

Google Advanced is probably the best place to search for almost anything, such as the names of scientific papers, if trying to find a copy which is freely available on the Net:
The AdsAbs service is absolutely fabulous!  Here are listed the key details of astronomy, astrophysics and physics papers going back over a century, including in many cases .PDF versions of the entire paper.
The Search button leads to multiple pages for searching, based on author, title, date etc.  "Browse" leads to Journal/Volume/Page Service, and with the right journal code, volume number and starting page (or no page numbers to see the entire volume) the listings of articles can be found:
To find the journal codes, this list has clickable links which lead to the above page with the code already set in the form:

There are also scanned books at: including a general introduction to astronomy and astrophysics and another on stellar astrophysics.

Preprints - including papers which have not been published, or are not even submitted to journals, can be found at:

Usenet newsgroup sci.astronomy seems to be rather dormant: .  The action is in 8 sci.astro.* newsgroups: .  In particular:
I haven't been reading this - I should catch up and contribute.

Grzegorz Wardzi?sk's Astrophysics for Busy People
is a site I should read in detail:
This is a daily list of new papers, with direct links to .PDF copies, automatically prepared from which is a mirror of  The archive of daily lists, going back to October 2002, is at: .

The list of Astronomical Newsletters:
The Active Galaxies Newsletter - lists papers recently accepted for publication:
The Blazar Times (BL Lacs too):

A reference site with a vast amount of constantly updated material - but what does it cost to subscribe?
The Encyclopedia of Astronomy and Astrophysics
Ed P. Murdin
Nature Publishing Group and Institute of Physics Publishing
There was a print edition in 2001, but it is (April 2004) out of print: . 2,197 pages in four volumes.  There's a copy at the Melbourne Uni Physics Library . . . and one is available at #Bookfinder .

If you need to convert a PostScript file (.ps), as is used by many academics for their papers, into a .PDF (Adobe Portable Document Format) file so you can view and print it with the freely available Acrobat Reader (Wherever the "Get Adobe Reader" is at . . . It is not called "Acrobat" any more . . . ), then you can save the .ps file to your hard-drive, and use the free service (based on open-source Ghostview software) at:
The resulting PDF can be viewed from that site, or (shift-click) saved to your hard drive.  (Search-engine bait: convert postscript to pdf conversion )

Websites - specific topics

Bill Keel's site has a great deal of fascinating and regularly updated material on galaxies, quasars etc.  There are many images and links to other sites.  There is also discussion of theories and observations which challenge the conventional theories.

The main text pages with the really gutsy material is at:

A set of pages of images and discussion of quasars and AGNs is:

Ned Wright's Cosmology Tutorial is constantly updated and explains Big Bang cosmology.  He is also active in discussions on sci.astro.research (see above #Usenet).
One page of his is "Errors in Tired Light Cosmology": (which, by the way, makes Google food: ).   See below for the debate between Ned Wright and Eric J. Lerner.

Lyndon Ashmore has a site with papers regarding the relationship of the CMB to the Hubble constant.  Tired light is involved in some of this - .  I haven't looked into this yet. (Added 2004 Nov 8.)

Astronomy Picture of the Day, with archives:

Current solar images:

The following items don't directly relate to plasma redshift or quasars, but I mention them because they concern alternative views of physics.

The Canadian physics journal Apeiron has a list of past articles, with all those after 1992 being available as .PDFs:
and a list of books:

The late Caroline Thompson maintained a lively and thoughtful site with her own theories, discussions and links to other resources - concerning "what is wrong with Fundamental Physics".  Her passing was announced in sci.physics on 11 February 2006.

Robert S. Fritzius
has a wide-ranging site:
including an excellent and well-referenced treatise / review article on the galactic dark matter missing mass problem: .


I read this introduction to astrophysics and astronomy and found it fascinating and valuable:
Introductory Astronomy & Astrophysics
Michael Zeilik
and Stephen A. Gregory,
4th Ed, Brooks Cole, 1997

The two most up-to-date books on quasars / active galactic nuclei are these two.  I think they compliment each other well and that it is well worth reading them both.
Quasars and Active Galactic Nuclei - and introduction
Ajit K. Kembhavi
and Jayant V. Narlikar
Cambridge University Press, 1999
Free chapter - the Historical Background:
Author contact details
Jayant V. Narlikar's home page:

This was probably completed in late 1997, judging by the references, and the mention (p 277) of a satellite due to be launched in 1998.  The authors generally follow the Big-Bang-Doppler-proportional-to-distance framework, but periodically remind readers how much easier it would be to explain quasar luminosities, jet and lobe sizes, superluminal motion, variability etc. if the the quasars were really much closer than is generally believed.

Active Galactic Nuclei
Julian H. Krolik
Princeton University Press, 1998

I am half-way through reading this and am also finding it fascinating. Subtitled "From the Central Black Hole to the Galactic Environment", this book seems to be primarily focused on theory, with really detailed treatises on black hole accretion discs, radiative transfer etc.  As far as I know, there is no questioning of the Big Bang theory - all objects are assumed to be at the distances implied by a conventional Doppler interpretation of their redshift.  Some references are to 1998 papers, so I guess the manuscript was finalised in mid 1998.

The author's homepage has some errata (in PostScript, so use the #PostScript-PDF converter below),

Another book, slightly older, which I have not read, is:
An Introduction to Active Galactic Nuclei
Bradley M. Peterson

1997, Cambridge University Press

Halton Arp's ( ) second book is:
Seeing Red - Redshifts, Cosmology and Academic Science
Halton Arp
Apeiron ( ) 1998
Halton Arp is the most prominent of the few astronomers who publicly question the conventional Big Bang and Doppler interpretation of the redshift of galaxies and quasars.  An observational astronomer with a huge body of widely used work spanning many decades, it seems that he has now been cast (in the minds of most astronomers) into what might as well be the Oort Cloud - far beyond the zone of conventional warmth and light, which is reserved for those who do not seriously question the Big Bang.

He presents many cases of apparent close physical associations of low redshift galaxies with high redshift quasars, which would only be possible if the redshift of the quasars was largely intrinsic, which would be a severe or fatal blow to the Big Bang theory.  It is my understanding of his position that there can only be one explanation of this intrinsic redshift: that the quasars are made of recently created matter, and that the mass of matter increases with its age (according to a theory about Mach particles exchanging mass) - which (supposedly) explains their intrinsic redshift.  In this theory, as far as I know, there is no place for black holes, or any other explanation of redshift, such as tired light theories, which include plasma redshift.  I find this insistence on only one possible explanation for the discordant observations to be unfortunately unscientific.  But the observations are important.

I just noticed (April 2004) that Halton Arp has a new book:
Catalogue of Discordant Redshift Associations
Halton Arp
Apeiron ( ) 2003

An older book challenging the Big Bang theory is:
The Big Bang Never Happened : A Startling Refutation of the Dominant Theory of the Origin of the Universe
Eric Lerner ( )
1991, Vintage reprint with new preface 1992
One part of Eric Lerner's thesis, if I remember it correctly, might be summarised: the large scale structure of galaxy clusters could not have possibly formed in the approximately 15 billion years in which the Universe has supposedly been expanding.  This seems reasonable to me, but I haven't thought about it in detail.  In early 2004, some new observations of galaxy clusters in what was supposedly the very early universe showed similar structures, (to-do: find the reference) and the researchers figured they had to radically revise their theories of galaxy formation to explain how such things could form in only one or two billion years.

Eric Lerner mentions (p 428) Paul Marmet's atomic/molecular hydrogen redshift theory, and points out how this doesn't work for the "Hubble shift" since it can be reliably shown that there is not enough neutral hydrogen in the IGM.  (To-do: where is the reference to lack of neutral H absorption setting an upper limit of neutral H in the IGM of about one atom per cubic kilometre?)  In the end, as I recall it, he doesn't claim to understand the origin of the Universe, which strikes me as a perfectly realistic, scientific position.  Also, he can't find a good explanation for the redshift - and devotes an appendix to this vexing question. 

I found this book fascinating for its history of the Big Bang theory, and the demise of now discredited theories which were equally widely upheld despite mounting challenges.  His book also has a history of how the Cosmic Microwave Background radiation came to be seen as evidence for the Big Bang.

Eric Lerner's site contains a concise statement of his theories with updates and responses to critiques, such as which is a response to Ned Wright's .  I find it puzzling and troubling that (as far as I can see, and I haven't searched exhaustively) neither Eric Lerner nor Ned Wright do each other - or the reader - the courtesy of linking to each other's websites.

Another book criticising the Big Bang theory is:
Bye Bye Big Bang: Hello Reality
William C. Mitchell
Cosmic Sense, 2002
A review is at: .  This looks like it could be a useful history and critique of the theory. (This lead me to a book called "Extended Electromagnetic Theory-Space-Charge in Vacuo and the Rest Mass of the Photon. By B. Lehnert and  S. Roy, which is reviewed by Stanley Jeffers at: .)

Another one of the author's 37 books is from 1995: The Cult of the Big Bang .

Here are three books on quasars which are primarily of historical interest.  However, I think there is real value in recognising the difficulties these objects presented when first discovered.  They do not fit well into accepted theories, and if anyone believes that quasars and the Big Bang theory are happy bedfellows, then I think it is by just getting used to the idea for too many decades.  These older books can generally be purchased via at, as noted below #Bookfinder .
Quasi-Stellar Sources and Gravitational Collapse
- Including the Proceedings of the First Texas Symposium on Relativistic Astrophysics
Ed. Ivor Robinson, Alfred Shild and E. L. Schicking

University of Chicago Press 1965

This is a fascinating and historical document of the big meeting in December 1963 which brought the key people together to discuss the radical new discovery of quasars - by radio and now optical signals, including the unprecedentedly high redshifts. 

Check the facsimile copies of the Nature papers and chart recorder graphs from the Parkes Radio Telescope ( ) when Cyril Hazard and co-workers used several lunar occultations to determine 3C273's exact location, the shapes of the two radio sources (core and jet) and the spectra of each source. 

(Unfortunately the Nature papers are not in AdsAbs.  They start on page 1037, March 16 1963.  Also worth getting on a trip to the library is Robert V. Wagoner's "Radio sources and peculiar galaxies" which is the first paper I know of to look for, and find, correlation between quasars and disturbed galaxies: Nature Vol 214, May 20 1967, pages 766 to 769.)

Also, nice long fold-out charts from Harlan J. Smith of showing the light curve of 3C273 derived from over 2000 plates, going back to before 1890.  It looks somewhat like a stock-market chart.

Here is appendix iii, the summary of the after-dinner speech by T. Gold - though I note that his characterisation of the 300 scientists as "men" is less than rigorously accurate, since Margaret Burbidge, and I imagine other women, were among the participants.
"It is my misfortune fo have to make a speech to you and yours to have to listen.  But many of you are in fact to blame - all those who the organizers in their wisdom had, in fact, asked before asking me.

First let me use this occasion to thank our hosts; let us also thank the organizations that donated funds for the meeting.  They all will get nothing in return other than a lot of papers and a chance to look at a bunch of confused and bewildered scientists.

This, of course, is a historic meeting.  It will be remembered as a meeting where these great new astronomical discoveries were first discussed.  It will also be remembered for the display there of strong men wrestling with even stronger facts.

It was, I believe, chiefly Hoyle's genius which produced the extremely attractive idea that here we have a case that allowed one to suggest that the relativists with their sophisticated work were not only magnificent cultural ornaments but might actually be useful to science!  Everyone is pleased: the relativists who feel they are being appreciated, who are suddenly experts in a field they hardly knew existed; the astrophysicists for having enlarged their domain, their empire, by the annexation of another subject - general relativity.  It is all very pleasing, so let us all hope that it is right.  What a shame it would be if we had to go and dismiss all the relativists again.

Texans will wonder what it is that they have got themselves into here.  These people who come here instead of concerning themselves with constructive aspects like "the impact of relativity on contemporary American thought" or "relativity and the American way of life" or perhaps even "gravitation and the search for oil."  Instead these people concern themselves with so obviously negative a topic as "Collapse: The Morbid Pathology of Matter."

The critics can now fortunately be silenced - I don't mean in the grand manner of the West - but they will be silenced by the discovery made by Harlan Smith that finally the elusive origin of the stock-market fluctuations has been found.  Stellar photometry will never again have to worry about financial support.

Now I must stop so people can go in the local tradition to their favourite club with their little brown paper bags."

Also, the first of four pieces from appendix iv - Quasi-Poetry:

At its far limits, the universe is daft.
Out edgeward nothing is itself no more:
Stars are no longer fat scuts of gas
But clots of stuff uncertain
As eccentric maiden aunts.

These lights called quasi-stellar,
Anarchic, observe not the curfew
Of thermodynamics: they run on
After they have run down, or
Shine with a brighter fire
Than they have fuel for.

That is not right.
For if I must pay for jot with tittle
And am not to be both big and little,
How is it they
Can play
According to neither Hoyle
Nor Boyle?

                                Howard McCord 

Fred Hoyle's book seems to be the second major book devoted to quasars. 
Galaxies, Nuclei and Quasars
Fred Hoyle

Heinemann, London 1965
There was no VLBI and the radio telescopes of the day could only narrow the location of a quasar down to a relatively large area of the sky, such as a degree or so.  On lunar occultation, which enabled the location of 3C 273 to be pinpointed, and then matched with an optical source, Hoyle writes (page 50, but I have added paragraph breaks):
"On an apparently very different front, Hazard had the following idea for determining the position of the radio source.  Sometimes the moon in its path across the sky crosses a radio source and blots it out.  Since one knows more or less exactly where the moon is at any given time, all that had to be done was to note with precision the moments of occultation and reappearance of a source. 

Working first at Joderell Bank on the source 3C 212, Hazard obtained a position that was correct to 2 or 3", an unprecedented achievement.  Then, going to Australia, and working with Mackey and Shimmins, he set about a similar determination for the source 3C 273. 

Sensing its importance, tremendous precautions were taken to carry out the observation.  Mention of these may be of some interest to you.  Several tons of metal were sawed off the telescope to permit observation at a lower angle of elevation than the normal operational range.  For hours before the occultation all local radio stations broadcast repeated appeals: that no one should switch on a radio transmitter during the critical period of the observation.  All roads leading anywhere near the telescope were patrolled to make sure that no cars were in motion in the vicinity.  A final, somewhat macabre touch: after the the observation Hazard and Bolton carried duplicate records back to Sydney, on two separate planes."

The third book on the subject, I think is well worth reading in full today:
Quasi-Stellar Objects
Geoffrey Burbidge and Margaret Burbidge
W. H. Freeman 1967
The diversity of ideas and the atmosphere of doubt and wonder of those early years strikes me as healthier than the current generalised notion that we know how far quasars are away, and therefore how old and luminous they are.  Quasars directly challenge the Big Bang theory, and this should be celebrated and pursued, rather than denied or ignored.  The problem is not with quasars or reasonable ideas about their nature - it is with the Big Bang theory which insists they are vastly older, brighter and further away than they really are.

There is also a less technical, more popular book from 1969:
In Quest of Quasars
Ben Bova 
( )
Cromwell Collier 1969
I am intrigued about the history of the term, and the concept, of "black hole".  The word does not appear in the indexes of these books, and I don't recall it appearing in the text of the Burbidge's book.  It seems that it became a widely used term around 1971 or so.

Two good, up-to-date, introductory books on the Sun and solar corona are:
Nearest Star - The Surprising Science of Our Sun
Leon Golub, Jay M. Pasachoff
Harvard University Press 2001

The Solar Corona
Leon Golub, Jay M. Pasachoff

Cambridge University Press, 1997

Two books on the solar transition region:
The Solar Transition Region
John T. Mariska
Cambridge University Press, 1993
I am reading this one.

Physics of the Solar Corona and Transition Region
Eds. Oddbjorn Engvold et al.
"A collection of papers from a workshop dedicated to an exploration of recent results on the solar corona, held in Monterey, CA, in 1999. The material is reprinted from Solar Physics, Volume 193, Nos 1-2, Volume 195, No. 1, No.2, and Volume 197, No. 2. For researchers and physicists. "  Kluwer 2001

The Cambridge Encyclopedia of the Sun is written by Kenneth R. Lang (who also wrote the two volume Astrophysical Formulae)

Thomas N. Lockyer
has a theory of particle physics which I understand as explaining fundamental particles such as the electron, proton and neutron in terms of charge in tight orbits.  He has two books, the second an update of the first.
Vector Particle Physics
Vector Particles and Nuclear Models
I have this book, but have not yet read it.  It would not surprise me if the current theories of particle physics, with quarks etc. might one day be replaced by something much more elegant. I also have the author's email address.  Here is a URL to search for discussions on Usenet newsgroup sci.physics.particle about his theories, many of which include his contributions: 

Thomas Smid has two sites of potential interest:

If you can't get these books new, then is an excellent place to find used copies.


Universe - The Cosmology Quest

This is a new (2004) video production from Norway, produced by Randall Meyers, which promises to be absolutely fascinating.

Some technical and TV sales details are at: .

The film is by Floating World Films (a totally Flash website).  Apparently it will be (is?) in three 50 minute segments for television.  There's a trailer there, in Quicktime.  (Follow: Media > Universe Documentary.  How I hate Flash!!!)
"A Feature-Film Documentary By Donald Goldsmith and Randall Meyers


This film tells the story of our attempts to understand the universe on the largest scales of distance, distances so great that they can only be estimated by indirect techniques. Because no direct measurements of these distances are possibly, all of the estimates we make must allow for the possibility of errors both large and small.

Most astronomers believe that any errors we now make in estimating the distances to faraway galaxies are relatively small. But in this film we shall also meet highly qualified astronomers who believe that most other astronomers are committing gross mistakes when they estimate the distances to faraway objects, and that these errors call into question the entire big-bang model of the universe.

The fact that a large majority of astronomers pay little attention to the objections to the big-bang universe raises important issues of how scientific research makes progress. These issues include the danger that the growing complexity of research tends increasingly to deny opportunities to those who do not support the views of the scientific mainstream.

Only time can tell whether the questions raised by a determined group of prominent astronomers, and rejected outright by the majority, will prove to be of crucial importance to the development of our understanding of the cosmos. Because scientists are human, they bring their humanity, for better or worse, into their scientific disputes. In this case, all sides have made human errors in attempting to influence one another?s views-errors that have left a sour taste among many astronomers, who refuse to take seriously the issues and controversial observations raised by the rigorous opposition.

This film attempts to show both sides of the continuing arguments, and the implications of those arguments, concerning the estimates that astronomers make of the distances to faraway galaxies. Although the film presents several astronomers and their struggles, its hero must be the truth about the cosmos, which has yet to emerge for certain."

The film itself has a site where DVDs can be purchased..


"Universe" is a unique mixture of a human interest and science documentary film. It exhibits a profound understanding of the scientific and human struggles in astronomy and cosmology during past decades, and is the first comprehensive film to deal with major new approaches in non-Big Bang cosmologies. Told with unbiased candor and simplicity, "Universe - The Cosmology Quest" is the story of the personal and scientific endeavor of a number of leading cosmologists to present different, if not more validated, explanations of the universe in which we all live, and to do so in a language both appealing and excitingly easy to understand.

Interviews with renown cosmologists Sir Fred Hoyle, Geoffrey Burbidge, Jayant Narlikar, Jean-Claude Pecker and Halton Arp as well as a pallet of extraordinary astronomers and scientific personalities such as Philosopher and telescope designer John Dobson, Jack Sulentic, Nobel Laureate Kary Mullis, and many, many others.

Divided into two chapters, 1: Quasars and the Discordant Redshift Problem, 2: The Theoretical Weaknesses in Big Bang Cosmology and Insights into the Plasma Universe; the film opens new doors for understanding the wealth of observational information and stimulating ideas which have arisen in recent years. The role media and professional prestige has played in forming and supporting this paradigm emerges, in what may be considered an exciting look into one of the most heated and interesting debates in science today.

"Universe - The Cosmology Quest", makes use of high-end 3D animations and motion graphics accompanied by an originally composed symphonic score and a full 6 track Digital stereo sound mix, making this documentary presentation - a feast for both the mind and the eyes!

According to a posting (2004-04-11) at by producer Randall Meyers, this two hour documentary is available on two DVDs, with "over three hours of the latest observations and a wealth of historical material". 

Solarmax ( ) is a 40 minute Imax movie from 2000 which features some fabulous SOHO movies (with dramatic sound effects) of the raging Sun - which is unforgettable as it rolls around on the screen, seething and churning, about 50 foot across!  However, the film is virtually a science-free zone.  It is worth seeing, I think, just for the SOHO movies, but I am really disappointed that it is so dumbed down for the supposedly dull and uninquisitive child or adult viewer, as if ordinary people have no capacity to understand the way the Sun works.  While the human history of solar worship and observations is fascinating, I would much prefer to see a movie devoted to solar researchers today, the outstanding questions and the many things which are known or theorised about our Sun.  For instance, time spent dwelling on the instruments of torture apparently used to extract Gallileo's confession could be better used for gutsy science! 

Update history

This page has grown in a rather untidy manner.  From 2003 October 23 to 2004 April 20 it resided at:
See for older versions.
It grew a great deal and was rather messy.  I tidied it up, added a substantial Introduction, and a table of contents and moved it to this new site on 2004 April 20.  (See for older versions.)  The old site contains previous versions of the page.  The update history below is for versions at the new site.  Older versions can be found in a directory /plasma-redshift-1/old/ . You will have to type this in manually to your browser.  I have not made a link because I don't want search engines finding the older versions.  The file names denote the date and sometimes the time.  I generally only note changes to the scientific content, not minor improvements to expression, or links etc.