Can Non-Cosmological Redshifts Explain Anomalies in Galaxy Interactions?

[Chronos]

It could be that quasars and AGN's are the only objects bright enough to be detected at such enormous distances [high redshifts].

 

[Garth]

Chronos - true, but there might still remain the problem of explaining the existence of well developed and evolved objects, quasars, AGNs and regular galaxies in the ultra deep Hubble field, at such an early stage of the universe's history. Perhaps the universe is older than we think?

Garth

 

[turbo]

Chronos - true, but there might still remain the problem of explaining the existence of well developed and evolved objects, quasars, AGNs and regular galaxies in the ultra deep Hubble field, at such an early stage of the universe's history. Perhaps the universe is older than we think?

Garth

Perhaps much older! (As in: "too much older to express numerically.") The galaxies that we see in the ultra deep field seem to be just like the ones surrounding us. Some small, some large, some with lots of internal structure, some interacting with others...that picture is in conflict with the heirarchical model of standard cosmology, as is the apparent surplus of high-redshift quasars. If high-redshift quasars are at the cosmological distances implied by their redshifts (in the standard model), they must be the most massive, condensed objects in the entire universe. How did those extreme concentrations of matter occur so early in the life of the BB universe?

 

[Nereid]

Guys, let's not get carried away here!

There's at least a decade of work - mostly good observations, across the EM spectrum - before anything definititive can be said about objects and structures in the first ~1 billion years after the surface of last scattering.

However, even with just the HUDF work - and not even considering X-ray, IR, radio, etc deep observations of the same field - there's precious little to suggest that

[t]he galaxies that we see in the ultra deep field seem to be just like the ones surrounding us. Some small, some large, some with lots of internal structure, some interacting with others...that picture is in conflict with the heirarchical model of standard cosmology, as is the apparent surplus of high-redshift quasars

... small, yes; interacting, yes; but IIRC, the first HUDF papers were quite clear that the early structure appears to be quite different from that of the local universe!

turbo-1: do you have a reference to 'the apparent surplus of high-redshift quasars'?

For the avoidance of doubt, I agree that these early studies of the early universe have produced fascinating results, which MAY end up being shown to be inconsistent with the concordance model, but it's early days (did I say that already?)

 

[turbo]

turbo-1: do you have a reference to 'the apparent surplus of high-redshift quasars'?

For the avoidance of doubt, I agree that these early studies of the early universe have produced fascinating results, which MAY end up being shown to be inconsistent with the concordance model, but it's early days (did I say that already?)

As recently as 10 years ago, researchers (including Hewitt, Foltz and Chaffee 1993) had concluded that the epoch of quasar formation was at z~3. Now, with better instruments, more sophisticated identifying techniques, and deeper surveys, discovery of very faint quasars with extreme redshifts yielding z~6 is no longer big news. Here is an example of how more sophisticated identification techniques can cause an explosion in the numbers of known high-redshift quasars.

http://scholar.google.com/url?q=http://www.edpsciences.org/articles/aa/pdf/press-releases/PRAA200404.pdf

Standard cosmology is still loaded with assumptions that were not too problematic in the light of z~3 quasars, but may be quite untenable with the identification of multiple z~6 quasars. When the Large Binocular Telescope comes on line, I predict that z~6 quasars will be left in the dust. There is a high-spirited race on to discover the oldest most distant objects, and the LBT is going to be irresistable to those researchers obsessed with high redshift objects.

As an example of the problems that the Big Bang has with high-z objects: X Fan, VK Narayanan, RH Lupton, MA Strauss, et al, in this paper studied three z~6 quasars - seen as they would have been about 800 million years after the big bang, if their redshifts are cosmological in origin. They calculate that the black hole cores of these quasars each has several billion solar masses.

Assuming that SDSS 1044-0125 is radiating at the Eddington luminosity, this object contains a central black hole of several billion solar masses. The assembly of such massive objects in a timescale shorter than 1 Gyr yields constraints on models of the formation of massive black holes (see, e.g., Haiman & Loeb 2001).

The authors also estimate that the broad emission line regions surrounding these quasars have super-solar metallicity. The paper is at this link:

http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001AJ...122.2833F&db_key=AST

Now, how did black holes with masses equivalent to several billion suns have time to form in less a billion years after the big bang? And how do we explain the metallicity of their environments so early in the life of the universe? How could enough massive stars have developed and gone supernovae in that 800 million years to provide metallicity of those environments equal to or greater that of our own, which has been metal-enrichened by billions of years worth of supernovae?

If quasars are the products of local ejection events, and have intrinsic redshifts that moderate as they evolve, these problems go away. If quasars are at the distances (and look-back times) suggested by their redshifts, these z~6 objects already place severe constraints on star formation and the development of structure in the infancy of the BB universe. Objects of greater redshift are likely to be found, and will strain the standard model even further.

 

[turbo]

small, yes; interacting, yes; but IIRC, the first HUDF papers were quite clear that the early structure appears to be quite different from that of the local universe!

Here is a link to a paper that identifies large, old, highly evolved galaxies in the HST UDF at z~3.

http://scholar.google.com/url?q=http://arxiv.org/pdf/astro-ph/0405432

It may well be that structure in the UDF appears different from that of our local neighborhood, but before we read too much into that one (glorious!) image, let us consider some of the things that affect the usefulness of that image. First off, at high redshift, the most visible objects will be the ones with the most concentrated, perhaps violent, activity (mergers, starburst, etc). Galaxies with more uniform diffuse star distribution and a nondescript galactic core, like M33, will not be as easily detected in the UDF at high redshift, due to low contrast. Small galaxies with modest luminosities will be underrepresented simply because our instruments cannot detect them. Galaxies that are highly disturbed and energetic will be overrepresented, so if we see lots of oddballs at z~3-6, we should not be surprised - it is predictable and it should be expected. This selection effect can cause a strong bias, especially as we approach the limits of our instruments' capabilities. Additional biasing factors include surface brightness dimming, reddening from intergalactic dust, selection of filters for our instruments, and selection of noise-reduction algorithms in image processing, to name a few. Again, it's a great picture, but its value as a cosmological tool is limited by these factors, and probably dozens more that I haven't thought of.

 

[Garth]

On the other hand turbo-1 it may be that the age of the universe needs only to be moderately adjusted to explain these early well formed objects.

Cosmic acceleration is still a very little understood phenomenon, applied to the early universe it would extend the initial 'singularity' back in time and could allow for all the time required for these objects to form.

As you know my preference is for the freely coasting, or strictly linear expansion, model R ~ t, which allows an extra third on the age of the standard Einstein - de Sitter R ~ t^2/3 model.

Garth

 

[turbo]

As you know my preference is for the freely coasting, or strictly linear expansion, model R ~ t, which allows an extra third on the age of the standard Einstein - de Sitter R ~ t^2/3 model.

Garth

Yes, I am well aware of that feature of SCC, and that modification would ease the constraints on the heirarchical model considerably. (At least until we build some LOTS bigger telescopes and more sensitive detectors!) Observational astronomy will eventually leapfrog cosmological theory in this regard, if recent history is any guide.

 

[Chronos]

Assuming redshift = distance, why would it be surprising quasars form an increasingly large percentage of the total population of objects as redshift increases? If the Arp is correct and quasars are ejected from galactic cores, then quasars are not brighter than the mother galaxy. So where are the mother galaxies for all the highly redshifted quasars?

 

[Wave's_Hand_Particle]

Yes, I am well aware of that feature of SCC, and that modification would ease the constraints on the heirarchical model considerably. (At least until we build some LOTS bigger telescopes and more sensitive detectors!) Observational astronomy will eventually leapfrog cosmological theory in this regard, if recent history is any guide.

May I suggest Galex? :http://www.galex.caltech.edu/

This is a recent group that have increased the puzzle as to , Quote:The recent discovery suggests our aging universe is still alive with youth. It also offers astronomers their first, close-up glimpse at what our galaxy probably looked like when it was in its infancy.

The linked site has a wealth of interesting data available.

P.S. click new press release.

 

[turbo]

If the Arp is correct and quasars are ejected from galactic cores, then quasars are not brighter than the mother galaxy. So where are the mother galaxies for all the highly redshifted quasars?

If Arp is correct, the mother galaxies for highly redshifted quasars are relatively nearby, and will not have the same redshift as the quasars. For instance, a quasar with a redshift of z~4 may have been ejected from a galaxy of z~2. As the quasar evolves, it gradually loses excess redshift. As it takes on the appearance of an AGN, it will still have some excess redshift relative to its mother galaxy.

 

[turbo]

May I suggest Galex? :http://www.galex.caltech.edu/

That is a very interesting site, and we'll likely get more surprises as the project matures. Since Galex is an all-sky survey project, it will complement other surveys done in other wavelengths. The discovery of massive, very young galaxies forming in our "backyard" ought to help some folks re-examine their rejection of Steady-State cosmologies with continuous creation.

 

[Garth]

For instance, a quasar with a redshift of z~4 may have been ejected from a galaxy of z~2.

In which case where are the corresponding quasars ejected in our direction with a redshift of z ~ -2?

Garth

 

[turbo]

In which case where are the corresponding quasars ejected in our direction with a redshift of z ~ -2?

Garth

In Arp's model, the excess redshift is intrinsic to the object. The spectral shift due to proper motion of the quasar will be a small factor. If a quasar is ejected toward us, its spectra will be redshifted due to cosmological redshift (appropriate to its real distance from us), and additionally redshifted due to its intrinsic properties. The blueshift due to the quasar's proper motion toward us will reduce the measured redshift just a bit. It will not result in an absolute blueshift.

 

[Chronos]

Expanding on Garth's question, where are the high z quasars superimposed in front of a lower z mother galaxy?

 

[turbo]

Expanding on Garth's question, where are the high z quasars superimposed in front of a lower z mother galaxy?

Such superimposed or apparently-connected high-Z objects associated with low-z objects are routinely dismissed by the adherents of standard cosmology as either chance projections or examples of lensing. Let's try this one example:

Take a look at the Einstein cross, and tell us what you see. There are four quasars of approximately the same redshift, that vary in brightness. They are not smeared out into arcs or circles, like other gravitationally-lensed objects, yet they are held out by conventional cosmoloists as the penultimate examples of gravitational lensing. They have varied in brightness very smoothly over a period of years, and one of the objects seems to be a bit of a contrarian, dimming while the other members are brightening. Microlensing has been cited as a possible cause of the differential, but if the lensing galaxy and the lensed quasar are very widely separated, brightness differentials that could be caused by microlensing would occur over a very short periods of time, not slowly and smoothly over several years.

 

[Chronos]

Theories that make predictions of what is seen must also predict what is not seen. Give examples of quasars superimposed over background galaxies with lower redshifts. I am not aware of any.

 

[Garth]

And if the high red shift of some quasars is doppler rather than cosmological then there should be some blue shifted quasars, ejected from relatively near - low z galaxies, coming in our direction.

And a Very Happy New Year!

Garth

 

[turbo]

Theories that make predictions of what is seen must also predict what is not seen. Give examples of quasars superimposed over background galaxies with lower redshifts. I am not aware of any.

I refer you to post #16 in this thread, which contains the following image link:

http://www.eso.org/outreach/gallery/vlt/images/Top20/Top20/top4.html

I also refer you back to post 46 at the top of this page. There are numerous images of the Einstein Cross all over the Internet, so I won't bother linking to one.

 

[turbo]

And if the high red shift of some quasars is doppler rather than cosmological then there should be some blue shifted quasars, ejected from relatively near - low z galaxies, coming in our direction.

And a Very Happy New Year!

Garth

A Happy New Year to you too!

In the Arp/Burbidge model, the large excess redshift of quasars is intrinsic, and is not due to proper motion (doppler effect). The amount of spectral shift due to proper motion is miniscule by comparison, so we should not expect to see any blueshifted quasars - and we don't.

Let's look at a simple model that invokes only gravitational redshift: A a black hole that has been ejected from a galactic core in a relatively naked state (it hasn't pulled along much material from the parent body). As the black hole accretes matter from the IGM, it will form an accretion zone. Matter in that zone will be excited, and will radiate. If the accretion zone is initially small and located relatively near the Schwartzchild radius of the black hole, radiation from that zone will be highly redshifted. This object has the following contributions to spectral shift:
1) cosmological redshift due to its distance from us
2) intrinsic gravitational redshift
3) spectral shift due to proper motion (doppler effect)
As the object gathers more and more matter from the IGM, its accretion zone grows. Radiation is emitted farther from the Schwartzchild radius, and is therefore not as strongly redshifted, reducing the contribution from factor 2) above. Gradually, the quasi-stellar object takes on the appearance of an AGN. This is my own (very simplified) mental model of the process. Others have proposed that newer objects are more redshifted than older objects for other reasons.

 

[Nereid]

HNY everyone!

If I may say so turbo-1, this Arp/Burbidge model has several fatal flaws, among them:

- it cannot account for the observed spectra of quasars, esp of high redshift ones. Think Lyman forest - what and where are the 'cold', discrete gas clouds which produce that forest? If you say they are clumps of IGM which are in the process of being drawn into the BH, then why don't we see evidence of such clouds anywhere else? The time (as measured by us here on Earth) for such clouds, already very very deep into the BH well, to be disrupted and join the accretion disk is way shorter than the decade or three for which they've been seen (to remain unchanged)

- the physical distance of the infalling/foreground clouds from the accretion disk - which will be emitting copious quantities of X-rays and gammas - will be quite small, so why aren't these clouds being heated, ionised, etc?

- if quasars are BH ejected from galaxies, why don't we see a huge excess of quasars in (or near) rich clusters? If the quasars are intrinsically rather faint, we should see an even greater degree of clustering (on the sky), near only the nearby clusters (and superclusters).

 

[turbo]

HNY everyone!

If I may say so turbo-1, this Arp/Burbidge model has several fatal flaws, among them:

- it cannot account for the observed spectra of quasars, esp of high redshift ones. Think Lyman forest - what and where are the 'cold', discrete gas clouds which produce that forest? If you say they are clumps of IGM which are in the process of being drawn into the BH, then why don't we see evidence of such clouds anywhere else? The time (as measured by us here on Earth) for such clouds, already very very deep into the BH well, to be disrupted and join the accretion disk is way shorter than the decade or three for which they've been seen (to remain unchanged)

Here is a helpful paper. The authors studied metal absorption lines in the spectra of high-redshift quasars and determined that the photoionization by the quasars themselves are likely responsible for the absorption effects.

While we concluded in §8.3 that there is clear indication from these comparisons that our observations are consistent with expectations of photoionization equilibrium, there is evidently also a strong evolutionary effect not reproduced by the assumed ionizing radiation model. Below, we explore the implications of our observations for the spectral characteristics of the ionizing radiation and move to a more general form of metagalactic radiation field containing contributions from both QSOs and galaxies, each with their own evolutionary behaviour.

8. We observe substantial evolution in redshift in specific combinations of ionic ratios, as follows:

9. At z . 2.65 we find that QSOs dominate the metagalactic ionizing radiation background and that contributions from galaxies have minimal effect. This requires a low escape fraction for ionizing radiation from galaxies, fesc . 0.05, consistent with other observations.

10. At z & 3.4 we find that neither QSOs as dominant contributors to the metagalactic background, nor a high opacity in the He ii continuum, can explain the observed ionic ratios. Between z = 2.65 and z = 3.4 there is evident transition in the ionization properties of the absorbers, with large scatter.

If their observations are borne out, absorptive features in quasars' spectra may prove to be local effects. The fact that there is an evolution in quasar spectral features with redshift is a problem for standard cosmology, but is supportive to the ejection/evolutionary model of quasars. If quasars lose apparent redshift by gathering matter and forming growing accretion zones, it may be that as the quasar matures, around redshift z<3 it becomes capable of photoionizing its surroundings, causing the metallic absorption lines cited in the study.

Here is the paper.

http://citebase.eprints.org/cgi-bin/citations?id=oai%3AarXiv%2Eorg%3Aastro%2Dph%2F0307557

- the physical distance of the infalling/foreground clouds from the accretion disk - which will be emitting copious quantities of X-rays and gammas - will be quite small, so why aren't these clouds being heated, ionised, etc?

They are - see the paper above.

- if quasars are BH ejected from galaxies, why don't we see a huge excess of quasars in (or near) rich clusters? If the quasars are intrinsically rather faint, we should see an even greater degree of clustering (on the sky), near only the nearby clusters (and superclusters).

Has such a survey been undertaken, and has it been proven that quasars do not appear preferentially aligned with active galaxies? Arp and Burbidge have cited many such apparent quasar/galaxy clusterings and alignments over the years, but each example has been pooh-poohed as "chance alignments" selection bias" etc. Conservative cosmologists are convinced that such physical associations cannot exist, so they are certainly not going to spend any time and grant money disproving such associations. Are you aware of any papers offering observational evidence that such associations (quasars preferentially near local galaxies) cannot exist? I would be very interested in reviewing any such papers.

 

[Nereid]

Thanks turbo-1, a quite lengthy (127 pages) and detailed paper.

Indeed, the absorbers (the gas clouds between the quasar and us, which are responsible for the Lyman forest, and various absorbsion line systems of C IV etc) have been photoionised and are not cold.

The model which Boksenberg and Sargent base their work on is as follows:
- quasars are objects as distant as their (cosmological) redshift
- between the quasar and us are a number of gas clouds, are responsible for the absorption line systems in the quasar spectra, also as distant from us as their (cosmological) redshift
- the detailed spectra of a number of the metal systems are reliable indicators of things such as the local (in the vicinity of each cloud) radiation environment, gas temperature, and gas composition.

Their analysis of the detailed spectra of several quasars - at a range of redshifts - leads them to conclude:
"... find d = 31–85 kpc as the implied distance range for the absorbers[/color]" (from local - i.e. near the respective clouds - galaxies) - IOW, the absorbers are likely (in) the halo of galaxies
"... for our sample the C IV clustering is entirely due to the peculiar velocities of gas present in the outer extensions of galaxies[/color]"
"... the majority of absorbers are photoionized and find that at z <~ 2.65 QSOs dominate the ionization of the absorption systems whereas at z >~ 3.4 an additional, dominant contribution from galaxies with specific spectral characteristics and high radiative escape fraction in the energy range 1–4 Ryd is required.[/color]".

However, quasars are only 'local' ionisers for the clouds in the sense that the clouds are ~10 to 100 kpc from a local (= has a very similar redshift to the cloud) quasar. They do NOT mean the clouds are 'local' to the quasar which is providing the illumination (so that we can observe the lines)!

But we can use these results to constrain the 'quasars exhibit substantial gravitational redshift; the absorption features are clouds around the quasar, but not as deep into the well' idea: AFAIK, the clouds observed near the Milky Way's SMBH (several million sol?) show NO gravitational redshift, even though they are within a few ly (at most) of the SMBH. So, how could a quasar exhibit such an enormous gravitational redshift (in the Arp-Burbidge idea), and have quite a few clouds (with internal motions of just a few 10s of km/s) so close to the BH that they too have huge gravitational redshifts?

 

[turbo]

Thanks turbo-1, a quite lengthy (127 pages) and detailed paper.

Indeed, the absorbers (the gas clouds between the quasar and us, which are responsible for the Lyman forest, and various absorbsion line systems of C IV etc) have been photoionised and are not cold.

The model which Boksenberg and Sargent base their work on is as follows:
- quasars are objects as distant as their (cosmological) redshift
- between the quasar and us are a number of gas clouds, are responsible for the absorption line systems in the quasar spectra, also as distant from us as their (cosmological) redshift
- the detailed spectra of a number of the metal systems are reliable indicators of things such as the local (in the vicinity of each cloud) radiation environment, gas temperature, and gas composition.

However, quasars are only 'local' ionisers for the clouds in the sense that the clouds are ~10 to 100 kpc from a local (= has a very similar redshift to the cloud) quasar. They do NOT mean the clouds are 'local' to the quasar which is providing the illumination (so that we can observe the lines)!

Ah, but let's for the moment assume that quasars have intrinsic redshifts and are relatively local. In light of this, the interpretation of their results takes on some interesting twists that are consistent with the ejection/evolutionary model of Arp and the Burbidges.

As to the meaning of the results as interpreted in standard cosmology: by what mechanism do quasars as distant as z~2-3 (cosmological redshift only) suddenly lose the ability to photoionize the absorbers? This is a significant puzzle. Although they are very faint, quasars at z~6 have been studied (~800My after the Big Bang). Putting them at cosmological distances in accordance with the Hubble relation, these quasars each have masses equivalent to hundreds of billions of suns, with immense luminosities, and interestingly, with solar and super-solar metallicities. (from post 35 above)

http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001AJ...122.2833F&db_key=AST

 

[turbo]

If quasars are the products of local ejection events, and have intrinsic redshifts that moderate as they evolve, these problems go away.

That was from a previous post in this thread, citing quasars with super-solar metallicities and masses equivalent to several billion suns. There are other problems that will become resolves if quasars can be shown to have large intrinsic redshifts. Two such puzzles relate to a single object: 3C147. 3C147 is a radio-loud quasar (over 2000 times stronger than CenA or VirgoA) with a very intricate and rapidly changing structure. It has been the subject of much study, and in fact is the subject of a recent VLBI observation regarding its polarization, intensity and rotation:

http://xxx.lanl.gov/pdf/astro-ph/0412653

What is so interesting about this quasar, apart from it's radio strength? For one thing, two components in its interior are currently separating from one another at faster than the speed of light. The other interesting fact is that 3C147 is in the error box of a 320 EeV cosmic ray detected by the Fly's Eye. This is the strongest cosmic ray every detected, and although 3C147 was initially implicated, it was discarded as a potential source, because it was though to be too far away at over 100 Mpc.

If 3C147 has intrinsic redshift and is much closer than its z>.5 implied distance, these puzzles are solved. The internal features are separating at less than the speed of light (whew! ), and we have a very likely source for the 320 EeV cosmic ray. For an idea of the power of this cosmic ray, click on this link:

http://www1.ast.leeds.ac.uk/haverah/ev.shtml

There are other anomalies that can be resolved if quasars have intrinsic redshifts and are substantially closer to us that is implied by the Hubble redshift/distance relationship. I can trot out more of them if anyone cares to discuss them.

 

[Chronos]

I refer you to post #16 in this thread, which contains the following image link:

http://www.eso.org/outreach/gallery/vlt/images/Top20/Top20/top4.html

I also refer you back to post 46 at the top of this page. There are numerous images of the Einstein Cross all over the Internet, so I won't bother linking to one.

Apparently I missed something. Which quasar is superimposed in front of NGC 1232? The ESO article you reference makes so such suggestion. I am also not aware of any claims that a quasar is superimposed in front of a lower redshift galaxy in the Einstein cross. Please identify or give a link providing IAU catalog numbers for such objects. And more importantly, why are there not hundreds of such examples. If quasars are ejection events, should not about 25% of them be line of sight superimposed in front of a lower redshifted mother galaxy?

 

[Nereid]

I would like to return to the specific question of whether quasars' redshifts are (mostly) cosmological or not ... i.e. are they at (approx) the distance which their redshift+the Hubble relationship implies?

AFAIK, there are only three competing ideas, none of which has much support in the mainstream journals (as in, lots of papers exploring the idea, finding corroborating observational results, etc) - CREIL, plasma cosmology, and 'galaxy ejection'.

In the first, quasars are neutron stars in the Milky Way, with a dirty hydrogen cloud in/around them.

I haven't read enough of Ari's paper to be able to say what they are in the second.

In the third - the only one for which we have a defender here in PF - they are near-naked BHs, a few to a few hundred (?) Mpc away, accreting matter from the IGM.

(To be sure, quasars may very well pose some serious challenges for the concordance model of cosmology - how to account for such massive objects so early? However, these are considerations for another thread).

I'm curious as to whether anyone has tried to make a serious attempt to show that the naked BH accreting IGM matter is consistent with observations - anyone? I'm thinking of things like:
- how much mass would a naked BH accrete in the IGM? (presumably it will vary by BH mass, density of the IGM, and maybe the BH's speed through the IGM)
- how close to the event horizon would the accretion disk be?
- what would account for the quasar jets?
- if we could observe it, what would the redshift of such jets be? (presumably they would not have any measurable gravitational redshift - at a distance of ~Mpc from us (say), they'd be ~kpc from the quasar BH)

 

[Chronos]

I have no problem with SMBH or super massive primordial stars [think hypernovas] in the early universe. Gravity was just beginning to flex its muscles and matter density was very high back in those days. Feeling bold, I think that a great deal of the apparent missing matter may reside in such objects. Perhaps not enough to shove aside the deuterium problem, but it might close the gap.

 

[turbo]

Apparently I missed something. Which quasar is superimposed in front of NGC 1232? The ESO article you reference makes so such suggestion.

No the ESO article does not make such a suggestion, and I would be shocked (although pleased at their braveness) if they pointed out the widely disparate redshifts of these apparently interacting objects. Unlike objects that have been ejected along the rotational axis, these objects have apparently been ejected along the galactic plane (like M51's partner) and have had plenty of opportunity to strip material from it's parent galaxy. While the compact object directly above the galactic core is not quasi-stellar in appearance, it has a HUGE apparent recessional velocity.

Here is a nice picture of NGC 1232 and apparently ejected companions. If we assume that redshift is due to cosmological expansion, NGC 1232 has a apparent recessional velocity of 1776 km/s. The small distorted companion at the lower left has an apparent recessional velocity of 6552 km/s. The tiny bright clump located just about halfway between the core of the host galaxy and the top border of the image may be following a similar ejection path, but it has an apparent recessional velocity of over 28,000 km/s, nearly 1/10th the speed of light.

http://www.eso.org/outreach/gallery...Top20/top4.html

The physical association of objects with disparate redshifts requires that we explore the possible mechanisms causing non-cosmological redshifts.

 

[turbo]

I am also not aware of any claims that a quasar is superimposed in front of a lower redshift galaxy in the Einstein cross. Please identify or give a link providing IAU catalog numbers for such objects. And more importantly, why are there not hundreds of such examples. If quasars are ejection events, should not about 25% of them be line of sight superimposed in front of a lower redshifted mother galaxy?

First off, the components of the Einstein cross are changing over time. Their long-term luminosities and colors are diverent. This is claimed by some to be a product of microlensing. There are also very short-term variations in the luminosities and colors of the components that are not seen in the light-curves of the other components. Interestingly, these are also cited as examples of microlensing. There is no hint of arc-shaped distortion in the four images. I could build you a system of four wedge-shaped prisms that could produce 4 point-like images of a distant source. I don't think I could begin to design a lenticular lens (modeling the central mass of that face-on spiral) that could produce these point-like images without arc-type smearing.

Here is a paper regarding uncorrolated brightness and color variations in the four components of the Einstein Cross.

http://arxiv.org/abs/astro-ph/0312631

And here is a graph of the long-term luminosity curves of the four components. Note the uncorrolated long-term luminosity swings, especially in components A and C, and the steady decline of B, initially the 2nd brightest object to being the least luminous. Uncorrelated luminosity and color changes over both short and long terms are problematic for the lensing model. It is likely that these four objects are related high-redshift objects ejected from the lower-redshift face-on spiral. They are four separate (although similar) objects and they are evolving.

http://arxiv.org/PS_cache/astro-ph/ps/0312/0312631.0104_f2.gif