Due to time constraints and my desire to do things thoroughly or not at all, as of 13 April 2005 I am putting this project on the backburner for a while.
Please read the page:
../backburner/for my current thinking on sparse-particle redshift and scattering, latest updates and links to sci.astro.research and sci.physics.research Usenet newsgroups where significant discussions have taken place.
This is page is primarily directed at specialists in astronomy and astrophysics - but there are some explanations in blue for non-specialists. (Non-specialists: please see the Resources and Links section of my Plasma Redshift page for lots of resources which are assumed to be known in the following discussion, such as AdsAbs and Arxiv.org .)
First I discuss the main principles on which the Big Bang Theory (BBT) rests, and suggest how the theory can successfully be disproven.
Then I list recent (2000 to 2004) observations and analyses which directly contradict the BBT - and then new and old ones which challenge or contradict it. Together, I think these observations consistently support an alternative model of a Universe which is relatively static - at least not "exploding" - and in which the redshift of light from distant objects is caused primarily by some non-Doppler process such as "Plasma Redshift". I then list two Plasma Redshift theories - one of which is my own - and the CREIL (Coherent Raman Effects on Incoherent Light) theory from Jacques Moret-Baily.
My aim here is to show that the Big Bang is a theory which needs to be abandoned, because it is completely incompatible with several lines of excellent observation and analysis. I am not so concerned with exactly what to replace it with. It is pointless to try to scientifically establish how the Universe came into being - since the mechanisms which created space, time, the physical forces, energy and matter cannot have involved any of these, and so are beyond our capacity to observe and probably to think about. All I want to do is work towards a theory which explains the Universe today, and as we observe it in the past, within the limits of what we can know.
Its not really necessary to find a better theory to make scientific progress - disproving a widely held theory and abandoning it is excellent progress. Another page on this site, my long page on Plasma Redshift, offers an alternative theory for the Cosmic Microwave Background (CMB).
The BBT has grown and changed since its inception - and it has been accepted pretty much, or entirely, as a fact by most astronomers and astrophysicists since the early 1960s. It is taught as a fact in most or all textbooks. While critics say the theory is so endlessly adaptable that it is not a theory but a dogma, the BBT does have some interlocking principles which make it a coherent, falsifiable, scientific theory. Disproving any one of these points renders the whole theory (as currently generally accepted) false.
A corollary of this is that quasars have no intrinsic redshift. More generally, a corollary of the BBT is that there is no mechanism by which light can be redshifted by the medium it travels through, and no way that light is intrinsically redshifted (except by rising up against a gravitational field).
- The Universe began from an "explosion" at a single point, a long time ago - such as the currently (2004) fashionable estimate of 13.7 billion years. ("Before" that, it is theorised there was no time or space - and maybe nothing else such as physical forces.)
- Since then, the matter in the Universe has been "expanding" - that is, from the perspective of any point in the Universe, all the other pieces of matter in the Universe (galaxies, quasars etc.) are moving away in all directions. (While there is debate about this expansion rate, and how this rate has changed since the BB, the theory predicts that on a cosmological scale, all matter is moving away from other matter at speeds approximately proportional to the distance - so the "explosion" continues.)
- The redshift of the light we receive from distant objects is primarily caused by the Doppler effect of this motion. Alternatively, this is not deemed to be motion, but the expansion of space-time, or the "Hubble flow". Either way, while there is a little gravitational redshift, and Doppler shift due to motions of emitting and absorbing matter relative to the local average velocity of matter, the rest of the redshift of distant objects is caused by this Doppler shift. This was originally developed with reference to galaxies, but since the discovery of quasars (and more lately Gamma Ray Bursters - GRBs) at "cosmological" distances (way, way, beyond the distance of the local galaxies), the BBT has included the requirement that quasars too are at distances which can be calculated from Big Bang cosmology and the recession velocity of the quasars, which is calculated from the redshift of their light.
A further corollary of the BBT, but rarely stated, is that light and other electromagnetic waves can and always do travel for billions of years in space (primarily the Inter-Galactic Medium - IGM) without losing any energy. This statement conceives of each packet of light as a "photon", with a particular quanta of energy. Reducing that energy in any way would redshift the wavelength of the photon.
The BBT involves several other strands of theory, which supposedly explain how the present-day mix of elements came into being, and the origin of the CMB. While some people regard these observations as proof of the BBT, there are many ways they could be explained without a Big Bang. Indeed, if it were discovered that the CMB came from some other mechanism than the purported "echo of the Big Bang" from (what might naively be called) the outer-limits of space-time, then I think the BBT would probably survive just fine. Likewise, if someone proved that the current understanding of the prevalence of elements was wrong, then I think the BBT would adapt and find some other explanation for the revised observations.
Here I will not tangle with either the BBT's predictions of synthesis of elements, or its predictions of the CMB. There are the infra-red, X-ray and gamma-ray backgrounds to consider as well . . .
I will concentrate on the question of the explosive expansion of matter, and the cause of the redshift we observe in the light of distant objects.
To summarise, if any of the following can be shown to be true, then the Big Bang Theory will be disproved - probably to the point where the entire theory should be abandoned. Here I am discussing the theory logically. In the minds of a majority of scientists, whether a theory is regarded as valid or not is another matter.
A - Show that galaxies, quasars etc. as we observe them today are not all moving away from each other and from Earth.This means that the BBT is entirely false, because it has never included any notion that there was a BB explosion and that movement eventually halted, leaving the Universe today and billions of years in the past (which is how we observe distant objects) in a state where it is not continuing its explosive expansion. This would mean that point B must be true - the redshift we observe, currently conventionally ascribed to Doppler, must be caused by another process.
B - Show that most or essentially all the redshift of light from cosmologically distant objects is caused by a process other than Doppler-shift.This could be done by establishing in the lab, or by experiment in space, that one or more physical processes do redshift light - and that these processes operate in the IGM (and probably in other settings) in a way which explains the cosmological redshift without any requirement for motion away from us and therefore Doppler redshift. Alternatively, it could be proven by establishing point A.From this it follows that proving any one of the following would entirely disprove the BBT by proving point B above:
- That quasars of a given redshift are not as far away as galaxies of the same redshift. This would show that quasars have intrinsic redshift, which means there must be a potent non-Doppler redshift mechanism which is not currently recognised. That being the case, not only is the BBT seriously flawed due to its current insistence that quasars are at vast distances and therefore are very old and hugely powerful, but it will probably prove to be entirely wrong, since the new redshift mechanism will probably explain the redshift we observe in distant galaxies. (A paper discussed below, on the intrinsic redshift of certain types of galaxy, is particularly pertinent.) Ever since the discovery of quasars in the early 1960s, a number of strong arguments have been raised that they are not as far away as their "redshift distance" implies. I list as many as I can of these below.
- That some types of galaxies have a different redshift from others, when at the same distance. Again, this would prove there is a significant non-Doppler redshift mechanism.
- That high redshift quasars are ejected from, or are in physical proximity with, low-redshift galaxies. More generally, that any object with a certain redshift is physically close to, and not moving fast with respect to, some other object of a very different redshift.
- That quasars exhibit proper motion which is so high as to be inconsistent with the great distances calculated by the BBT "redshift distance" theory. Since we don't expect them to be moving vastly faster than galaxies at such redshifts, this would be good evidence that the quasars are much closer than currently believed, and that therefore a lot of their redshift is intrinsic.
Mike Hawkins' observations and analysis which show this are contained in one 2001 paper, which was published as a Letter in the Astrophysical Journal. To my knowledge this has never been successfully challenged. Indeed, it seems to have been generally ignored, apart from those papers I list below. Please note that the author does not, apparently, consider his work to be a disproof of the BBT. I do, and I wrote to tell him so on 2004 July 20! (The boldface link is where you can find the full paper, even if you have no access to the locked up versions at the journal site.)
Note for non-specialists
If the Big Bang theory is true, then the more distant an object is, the faster it is moving away from us. We therefore expect two things: redshift of the light and time-dilation of all events we observe from that object. Really the two things are the same - redshift to longer wavelengths is simply the light arriving at our telescopes or eyes at a different frequency to that with which it originated in the quasar. The Big Bang assumes that there is no other cause of redshift. According to this theory, when we observe light from an object which has a redshift of 0.7, its light has a wavelength of 1.7 times its original wavelength and its frequency is 1/1.7 of what it originated at. Similarly, if we could view a second-hand of a clock ticking near that object, we would expect to see the hand move once every 1.7 seconds, from our point of view.
Quasars are wild and crazy objects, which have been enthralling and perplexing astronomers since they were first observed visibly and had their high redshifts measured in 1963. They have extremely broad-band emission of electromagnetic radiation - from radio waves with tens of centimetre wavelengths right through the visible light band and into the x-rays and gamma-rays. This is a range of frequencies spanning a range of at least 1012 - see the first diagram here: http://obswww.unige.ch/3c273/ . In contrast, a star, or a galaxy of stars, has a much narrower range of emissions, due to their output being primarily a Planck black body spectrum, based on their surface temperature.
Quasars are widely (and I think correctly) understood as generating their emissions primarily by the synchrotron process - energetic electrons in magnetic fields. The widely accepted (and I think completely correct) theory is of a maelstrom of matter surging around the black hole and emanating this broad-band of radiation. Quasar output, as we observe it varies considerably. Individual quasars vary in different ways, of course, but if one has a large enough, well selected, population of quasars, the statistics of the way the change should be a relatively robust body of data which shows the average behaviour of "quasars" (however defined). By analysing the variation over many years, at a given wavelength, it is possible to draw a time vs. flux (amount of light received by the detector in the telescope) curve spanning, for instance, 20 or 30 years. In the case of 3C 273, the most prominent quasar, measurements of old plates provide a light-curve going back to around 1890.
Fourier analysis is a method of analysing this curve to see what "frequencies" it is composed of. This is directly analogous to a graphic display of the energy of music at different frequencies which are popular in stereo equipment and especially software MP3 players. However, in this case, there is only one set of energies - not one changing every fraction of a second. Thus, for each quasar which has been observed for long enough at a given wavelength, it is possible to say that its light-curve contains X amount of variation at frequencies around one cycle per ten years, Y amount of variation at frequencies around one cycle per 7 years etc.
If you had enough such measurements of quasars, at various redshifts, then you would be in a position to analyse each of their Fourier analyses to see if the high redshift ones varied, on average, at a slower rate than the low redshift ones. (There are some corrections which need to be made, or at least accounted for, due to the fact that when we observe, for instance, 0.5 um green light on Earth from a quasar for which the light has been redshifted by 0.7, then we are seeing light which started off at 0.5 / 1.7 = 0.294 um, which is in the near ultra-violet. Since quasar light of shorter wavelengths varies, on average, faster than longer wavelengths, this observational bias which correlates with redshift needs to be accounted for.
If the Universe is expanding, then we expect the frequencies of the variations in light from high redshift quasars (the most distant and most rapidly receding according to the BBT) to, on average, vary slower in exact proportion to their recession velocity. Thus, we expect to observe "time dilation" - slowing - of the statistics of variability in quasars in direct proportion to their redshift, which (in the BBT) is directly proportional to their recession velocity.
Mike Hawkins is based in Edinburgh, and works with a vast library of digitally scanned photographic plates of certain areas of the sky, taken over several decades. He worked with the data to find hundreds of quasars which had been observed sufficiently for this sort of statistical analysis. Then, by spitting the quasars into high-redshift and low-redshift groups, and also into high observed luminosity and low, he was able to perform statistical analysis which should show, unequivocally whether there is time dilation in the variability of high redshift quasars. The Big Bang theory predicts that this will be found, but he finds no such time dilation at all.
In his 2001 paper, he does not seem to consider his finding to be a disproof of the Big Bang - he has another explanation, based on the variation of quasars not being intrinsic (a feature of the quasar itself) but caused by gravitational microlensing of the light between the quasar and Earth. In this model, dark, heavy objects such as compact dead stars, neutron stars or even black holes (but why aren't they visible as matter spirals into them?) bend the light of the distant quasar, sometimes concentrating more light into our telescope than normal. These objects drift through space and are theorised to be numerous enough and heavy enough to cause all the variation we see in quasars. It seems that this explanation would produce no observations which look like time dilation - but I question this. Below, I quote a paper which challenges Mike Hawkin's microlensing theory, and I use a number of arguments to do what I think is a thorough demolition job on it.
So I think this paper stands as a robust disproof of the Big Bang - but that is not what its author thinks! Also, it should be noted, that while no-one has found fault in his observations or analysis, this paper, while having been published in the Astrophysical Journal, has been almost entirely ignored.
Time Dilation and Quasar Variability
M.R.S. Hawkins http://www.roe.ac.uk/roe/staff/
ApJ, 553, Issue 2, L97-L100, 2001 June
Citations to this article:
Abstract:The text below is based on what I wrote to Usenet newsgroup sci.astro.research, on 2004 July 20, under the title "Quasar variation - no time-dilation found by Mike Hawkins". Please refer to the discussion there.
The time-scale of quasar variability is widely expected to show the effects of time dilation. In this paper we analyse the Fourier power spectra of a large sample of quasar light curves to look for such an effect. We find that the timescale of quasar variation does not increase with redshift as required by time dilation. Possible explanations of this result all conflict with widely held consensus in the scientific community.
Hawkins convincingly shows that the degree of optically observed luminosity variation - measured at frequencies such one cycle per 10 years to one cycle per fraction of a year - is not correlated with the quasar's redshift. He also determines the relationship between shorter wavelengths and faster variation - and shows that this can at best explain only a fraction of the observed effect. This is based on his own measurements of two decades or so of photographic plates - he is not relying on anyone else's observations or interpretations.
In his paper he seems unwilling to consider this findings a challenge to the Big Bang Theory:
Taking the various arguments outlined above at face value, and accepting the case against microlensing, there does not appear to be a satisfactory explanation for the absence of a time dilation effect in quasar power spectra. The arguments resting on an expanding Universe and cosmological distances for quasars seem beyond challenge. The argument against microlensing is not so secure.I think that the expansion of the Universe is not at all well established. At present this theory relies upon the absence of an alternative theory for the cosmological redshift, and the currently accepted interpretation of supernovae light curves. That's it as far as I can tell. I argue against microlensing below.
I see a parallel here with the researchers whose apparently assiduous research failed to find the expected Transverse Proximity Effect (TPE) with a
foreground quasar. (See the next section.) I see both the lack of TPE and this work on the lack of quasar time-dilation as separate, excellent, contradictions of the Big Bang Theory. But the researchers themselves either fail to consider this (TPE) or explicitly reject it (as Mike Hawkins does), preferring what to me and to many others seems an impossible alternative explanation. For the TPE people, it is that quasars turn on and off, or have very limited lifetimes. For Mike Hawkins, it is that quasar variations are caused primarily by the gravitational microlensing effects of many dark matter bodies traversing the line of sight.
I think that these researchers evident consternation at their own results, combined with what appears to be excellent research and data reduction, makes these two sets of research all the more convincing as evidence against the BBT.
Citations and critiques
(2004 July 20.) Below I chase citations to this paper and Google hits for its title. I found nothing of substance beyond the Jerry Jensen citation and what follows.
First, two citations from papers by the same author:
Colour changes in quasar light curves
Hawkins, M. R. S.
MNRAS Vol 344 Issue 2 Page 492 - September 2003
Naked active galactic nucleibut I don't think these add much to the original paper - they seem to pursue his microlensing theme.
M.R.S. Hawkins 2004 June 7
Here are two papers which seem promising.
Fourier Analysis of Gamma-Ray Burst Light Curves: Searching for a Direct Signature of Cosmological Time DilationHeon-Young Chang has some other papers of potential interest.
ApJ, 557, Issue 2, L85-L88, 2001 August
Can microlensing explain the long-term optical variability of quasars?
Zackrisson, E.; Bergvall, N.; Marquart, T.; Helbig, P.
A&A 408,17-25 2003 September
Although controversial, the scenario of microlensing as the dominant mechanism for the long-term optical variability of quasars does provide a natural explanation for both the statistical symmetry, achromaticity and lack of cosmological time dilation in quasar light curves.
They accept Hawkins' research and look for models which may justify microlensing as an explanation of quasar variability.
Here, we investigate to what extent dark matter populations of compact objects allowed in the currently favored OmegaM=0.3, OmegaLambda =0.7 cosmology really can explain the quantitative statistical features of the observed variability. We find that microlensing reasonably well reproduces the average structure function of quasars, but fails to explain both the high fraction of objects with amplitudes higher than 0.35 mag and the mean amplitudes observed at redshifts below one. Even though microlensing may still contribute to the long-term optical variability at some level, another significant mechanism must also be involved. This severely complicates the task of using light-curve statistics from quasars which are not multiply imaged to isolate properties of any cosmologically significant population of compact objects which may in fact be present.
The problems with microlensing seem to be severe enough to write it off as the major explanation for Hawkins' observations - but they don't seem to consider that the Universe may not be expanding.
I think Mike Hawkins' paper is important and should be discussed much more widely. Three years have elapsed and there seem to be no serious citations, critiques, or use of his work to critique the BBT other than what I list here, including Jerry Jensen's paper.
My critique of microlensing as an explanation for the majority of quasar variabilityIf we look at quasar variability purely in terms of the frequency domain - the result of a Fourier analysis of the time vs flux observations, then maybe a case could be made for microlensing explaining most or all of the variation, but Zackrisson et al. 2003 (above) found problems with the theory in the context of their understanding of the BBT.
My critique is based on the time-domain nature of the variation of the electromagnetic radiation observed from quasars. This is a loose critique, without the references and details expected in a scientific paper. To me, it is very clear and obvious - not a subtle or marginal critique. However, others would not agree, so to do it properly I would need to develop more quantitative arguments and cite a bunch of references.
The first argument is that it is common for the flux received on Earth or in satellites from quasars at differing wavelengths exhibits correlations, including correlations with time delays. I can't think how a gravitational lens arrangement, no matter how many microlensing dark matter bodies were involved, could cause differing variations in flux for different wavelengths. Even if I could imagine such a mechanism, I think I would find it impossible to imagine such variations at different wavelengths having correlations involving time offsets of any kind - seconds, weeks or months.
The second argument is that from all we think we know about quasars (a lot of which is false, I believe, because of the excessive estimates of their distance and power output), we have many reasons to expect variation at different wavelengths in ways which are broadly compatible with what we observe.
The third argument is a qualitative one, but it seems solid to me. An individual gravitational microlensing event, where a massive, and to us invisible, object passes close to our line-of-sight to a distant start, we get a highly characteristic brightening curve. The object may be a planet, or more likely a brown (or black . . . ) dwarf. It may also be a neutron star, or perhaps even a black hole (Recent Microlensing Results from the MACHO Project, Popowski et al. http://arxiv.org/abs/astro-ph/0304464 ).
For instance, from the just-mentioned paper:
and from http://www.arxiv.org/abs/astro-ph/0204282
Figure 4. Left and right panels show the observed light curves of events (108009) and (101041) by MACHO collaboration. The best fit of gravitational microlensing light curves are indicated in NUT (dashed line) and Schwartzschild (solid line) spaces.
Also, from Gravitational Microlensing in NUT Space Sohrab Rahvar, Mohammad Nouri-Zonoz MNRAS 338 (2003) 926
This shows the characteristic nature (as far as I know) of gravitational lensing. It also demonstrates that neighbouring wavelengths (red and blue) do not seem to be magnified differently.
Here are some quasar light-curves, for 3C 273, from
30 years of multi-wavelength observations of 3C 273The first one is a detail of a larger one here: 3c273-light-curves.gif and shows "light" curves over 24 years or so, in two microwave, two infra red and one visible range of wavelengths.
Türler M., Paltani S., Courvoisier T.J.-L., et al., 1999, A&AS, 134, 89
The 1992 spike in the 37 GHz or the 1988 spikes in 1.65 um or V are the features which most closely resemble a gravitational lensing light-curve, but there are several reasons to reject this explanation.
For all these reasons (and any one of them would be sufficient) I propose that gravitational microlensing does not contribute significantly to the general variation of electromagnetic radiation we receive from quasars.
- The shape is wrong - for the 1992 spike in 37 GHz, it is too pointy.
- Gravitational lensing should affect all wavelengths in much the same way. Instead, we see peaks at one wavelength only partially represented, or not at all, in other wavelengths.
- There is, to the eye at least, good evidence of two phenomena which (as far as I know) are commonly found in quasar variability, but which are not at all explicable by gravitational lensing:
- Broader (in time) rises and falls at longer wavelengths - for instance the narrow spike in V in early 1988, with a (perhaps broader) version at 1.65 um, with successively broader versions at the three longer wavelengths.
- Lag in the longer wavelengths - for instance a corresponding peak at 15 GHz which is about 11 months later.
- Given that microlensing events are expected to be generally uncorrelated, in timing, time-width and magnification gain, we would expect to see variation more closely resembling a superimposed series of such spikes - although the alignment of multiple gravitational lenses could be tricky to model.
Mike Hawkins' analysis is devoted to observations in the visible and near visible range, but there is no reason to think that these variations are caused by processes any different from what causes variation at other wavelengths, at least in terms of the question of whether they are intrinsic to the quasar or whether they happen en-route.
So I propose that Mike Hawkins' analysis is of genuine intrinsic variations in quasars - and that his long-held microlensing explanation cannot be accepted.
In the absence of any other extrinsic explanation, and in the context of the tremendous amount of detailed work which has gone into understanding quasars, AGN etc. which does generally account for the variations being intrinsic to the object and its immediate environment, I propose that Mike Hawkins' work stands as an excellent proof that his sample of high redshift quasars is not receding from Earth significantly faster than his low redshift sample.
Since there is every reason to consider these observations, data reduction and analysis to be reliable (at least I think it is brilliant, painstaking work) and since no-one has challenged it, despite the challenge it presents to either the entire Big Bang Theory, or the huge body of theoretical work which attempts to explain quasars, I propose that this work be regarded as reliable evidence that quasars are not receding from Earth. (This is on the basis that we reject the notion that all quasars are moving away from Earth at a common velocity - and since the high redshift ones are moving at the same speed as the low redshift ones, none of them are moving much at all.)
Unless these observations can be challenged, and I can't imagine how they could be systematically wrong in ways which entirely hide a genuine Big Bang pattern of quasar recession velocities, I regard this paper as incontrovertible evidence that the Universe is not expanding at anything resembling the rate required by the Big Bang Theory. Likewise, I regard it as an excellent proof that the redshift of quasars is not caused by Doppler.
Ordinarily - ideally with some replication of this research with different observations and perhaps by an different analysis technique - that should be enough to cause everyone to abandon the Big Bang Theory. If this research pointed to wholly different conclusions from all other research, this would be tricky - but it can be seen below that there is plenty of supporting evidence which also shows that the cosmological redshift is not caused by Doppler, and so that the matter in the Universe is not expanding at all like the Big Bang theory predicts.
See the ../backburner/ page for links to the sci.astro.research Usenet newsgroup where this was discussed.
Note for non-specialists
If the Big Bang Theory is true, then the redshift of light from galaxies and quasars is caused by the Doppler effect - and since the Universe is thought to be expanding, there is a direct calculation which can be made from an object's redshift, to its recession velocity, and then to the distance it was away from us when the light we observe today was generated. This calculation also produces the time the light has been travelling. This calculation has various forms, and it depends on several "constants" which are not determined with certainty. So Big Bang people will calculate different distances and ages for the light of a given redshift, depending on the cosmological model and cosmological parameters they chose.
I think this is all wrong, but we need to put it to the test.
If the Big Bang Theory is true then, apart from a small component of the redshift caused by local movement away from us compared to other objects at that distance and apart from another small component of redshift caused by "gravitational redshift" - light undergoing time-dilation and therefore having a lower frequency and longer wavelength - as it rises from an object with a strong gravitational field, all the rest of the redshift is caused by the recession velocity of the expansion of the Universe. This may also be called the "Hubble flow".
So if the BBT is true, then a high redshift object is further away than a low redshift object. Since we believe that objects such as galaxies and quasars (as best we know) are not moving relative to their neighbours at much more than a small fraction of the speed of light (say 0.01, or 30,000 km per second at the most) then when we are observing objects with redshifts such as 0.3, 0.7. 2.4 etc. the vast majority of that redshift must be caused by the "Hubble flow" - which means (all this is if the BBT is true) that we can determine the distance as smooth and ever-increasing function of redshift. Calculators for this are on the Web.
For instance http://sa1.star.uclan.ac.uk/~cph/redshift.html
Use "70" rather than "100" for HO - the "Hubble Constant", since this is closer to current estimates. This is, on average, in general, how many kilometres a second an object is moving away from us (again, if the BBT is true) if it is at a distance of a Mega parsec. A parsec is 3.2 light years - around the distance to the nearest star. The main visible part of the Milky Way is about 30,000 parsecs in diameter. Andromeda is about 54,000 parsecs in diameter, and is about 0.765 Megaparsecs distant.
So if we find a quasar with a redshift of 2.605, using the above-mentioned calculator with HO set to 70 km per Megaparsecs, and if we believe in the Big Bang Theory, then we "know" that the distance to the quasar is about 4056 Mpc (Megaparsecs) away from us, and that the light we observed was emitted by the quasar about 7.964 Gyr (Gigayears) ago - 7.964 billion years ago, which is, according to current theories (which I reckon are probably reliable) is well before the Earth was formed.
If we find a quasar with a redshift of 2.562, by a similar process, we "know" (if we believe in the BBT) that it is only 4029 Mpc away, and that its light was emitted 7.94 billion years ago.
Depending on the cosmological model, the redshift to distance relationship isn't exactly linear, but it is reasonably linear and the distance always increases with increasing redshift.
Of course, if most of the redshift of quasar light is generated by the quasar itself, or very close to it, then all the above is nonsense - the BBT is wrong and the redshift of a quasar's light has virtually nothing to do with its distance, or how long ago the light was emitted.
The Transverse Proximity Effect is an expected effect if we have a pair or quasars, close to each other from our point of view on the sky, where we believe that one quasar is at a greater distance from us than the other. This takes a bit of explanation . . .
For instance, if the BBT is true, then two quasars of redshifts (z) 2.985 and 3.33 which are 17.6 arc-minutes apart on the sky from our point of view, can be regarded as a foreground (z = 2.985 gives 4277 Mpc) quasar and a background quasar (z = 3.33 gives 4452 Mpc). These are the redshifts of two quasars known as Q0042-2956 and Q0042-2639 respectively.
One common feature of the spectra of quasar light is a long series of troughs of light which has been absorbed (according to theories which I think are correct) by neutral hydrogen in the space the light travelled through. This means hydrogen atoms - a proton with an electron in orbit.
(H2 molecules as hydrogen exists in on Earth, are not believed to form much in interstellar or intergalactic space, since when two H atoms join to form the molecule, the molecule generally spins very fast as a result of the impact, and with no other molecules of specks of dust to bang into and slow down, the molecule eventually splits due to the centrifugal force.) Neutral H only exists, even in tiny quantities, if it is cool enough, say below 20,000 K (Kelvin is degrees Celsius above absolute zero, which is -273.15 C) and if there is not enough UV light to give the electron in the atom enough energy to leave.
This particular series of troughs in the spectrum of a quasar is called the Lyman Alpha forest. I think it is caused by neutral hydrogen in space quite close to the quasar, where most of the redshift of this light occurs. If that is true, the the BBT incompletely wrong. According to the BBT, the redshift of light is caused entirely be the velocity with which the quasar is moving with respect to us. If there was some neutral H near us, moving at about our speed, we would see its Lyman Alpha absorption at a wavelength in the spectrum which is close to what it would be on Earth, in the UV part of the spectrum at 0.1216 um (1216 Angstrom). A photon of light with this wavelength has exactly the energy required to get the electron in an H atom from the lowest energy level to the one above, which is an energy difference of 13.6 electron volts. Two pages with good explanations of this are:
http://astron.berkeley.edu/~jcohn/lya.htmlIf there was neutral H in the line-of-sight from the quasar, very close to the quasar, before there was appreciable redshift of light, then we would observe a trough in the spectrum (absorption of light of a particular wavelength) not at 0.1216 um, but at this wavelength multiplied by one plus the redshift value. So for a cloud of neutral H at a redshift of 2.985, we would observe the Lyman Alpha absorption at 0.1216 * 3.985 = 0.484 um, which is visible green-blue.
According to the BBT, the long series of troughs we know as the Lyman Alpha Forest are created by a vast series of neutral H clouds in the Inter Galactic Medium (IGM), between the quasar and us. (Lets ignore how they got there, and the evidence that the IGM is at hundreds of millions of degrees . . . ) These clouds are all approximately at rest with their surrounding matter, in the form of galaxies and the occasional quasar. (Note, the BBT virtually insists, or at least assumes, that all quasars are inside relatively ordinary galaxies. But a defining characteristic of what we call quasars is that we cannot clearly see any such galaxy! The explanation? "They are so far away that the galaxy would be too small, and besides the quasar core of the galaxy is vastly brighter than the stars, so our telescopes can't see the galaxy clearly.")
If the BBT is true, then we can find pairs of quasars where the background quasar has some Lyman Alpha forest absorption at a wavelength which, again according to the BBT, proves that the neutral H which created this absorption is located at the same distance from Earth as a "nearby" (in the skyplane - as if the sky was the inside of a sphere) foreground quasar. So according to the BBT, a particular part of the background quasar's Lyman alpha forest absorption, if there is absorption at that particular wavelength, would be caused by clouds in the line-of-sight from the background quasar which are physically quite close to the foreground quasar. That is, the clouds (or potential absorbing clouds) are the same distance away from us as the foreground quasar.
The Transverse Proximity Effect (TPE) is a predicted effect by which the foreground quasar emits so much UV light that no neutral H can exist anywhere near it. Quasars emit lots of UV and lots of everything else - and the UV wavelengths are particularly good at being absorbed by neutral hydrogen atoms, and giving the electron enough energy to leave the proton entirely. This is "ionization" and what used to be an atom of neutral H is now "photo-ionized" to be part of the plasma - electrons and protons (and other nuclei) flying around too fast to ever get it together and become atoms.
So if the Big Bang Theory is true, then the Lyman alpha forest of the background quasar is created, or is potentially created, in a long line of space, part of which is close enough to the foreground quasar for that patch of space to have no possibility of containing neutral H. Therefore, if this is really how things are physically arranged (if they are arranged otherwise, then the BBT is wrong) then we should not see Lyman alpha absorption in a particular range of wavelengths, due to the foreground quasar photoionizing (ie. zapping, frying etc.) any neutral H atoms which would otherwise be there.
I think this is an excellent test of the Big Bang theory. But, as far as can be told from the papers written by the TPE researchers, they do not think in these terms at all. They seem to assume the BBT is true.
While there were initially some tentative findings suggesting that the TPE effect had been found with a number of quasar pairs, later and more extensive research questioned these findings - and most importantly failed to find it in a number of more promising quasar pairs. The key TPE researchers report that they do not find the Transverse Proximity Effect.
When I read their papers, I wrote to them (2004-04-21) saying why I think their research is a great disproof of the Big Bang - but have not heard back from them.
OK, specialists! To briefly summarise the above non-specialist introduction, the TPE is the expected absence of Lyman alpha absorption in the spectrum of a background(This is as far as I got in July 2004 with this page. The project is currently on the ../backburner/ .