Can Non-Cosmological Redshifts Explain Anomalies in Galaxy Interactions?

[turbo]

Interestingly, the SDSS interactive learning site

http://cas.sdss.org/dr3/en/

lists NGC 7603 and PGC 07041 as an interacting pair of galaxies, although their redshifts are very different.

Go to the page below and find the image of NGC 7603 and PGC 07041. Click on the image to use the SDSS viewer. Click on the center of each galaxy and see its properties in the window at the upper right (note the redshifts). Then click on the two small bright knots embedded in the connecting arm.

http://cas.sdss.org/dr3/en/tools/places/page5.asp

Arp, the Burbidges and others have been pointing out for many years that there are interacting celestial bodies with widely disparate redshifts, so there must be at least one strong cause for redshifts that does not arise from cosmological expansion or proper motion.

 

[Chronos]

This is one of the persistent few in the Arp collection of apparently interacting objects with disparate redshifts. A persistent few researchers, notably Gutierrez & Corredoira, have attempted to link NGC 7603 [z=0.029] with NGC 7603B [z=0.057].
http://arxiv.org/abs/astro-ph/0401147
http://arxiv.org/abs/astro-ph/0203466
This work has not drawn any interest from other researchers aside from Bell, another intrinsic redshift proponent whose work has also been largely ignored.

The lack of mainstream support for intrinsic redshift is not proof of anything. The mainstream has been known to be wrong in the past. Intrinsic redshift would, however, draw a great deal of attention if compelling evidence were found. It would obviously be a very mysterious phenomenon given current knowledge and scientists love a good mystery [not to mention the nobels for solving them]. The most reasonable explanation is the evidence for intrinsic redshift is not compelling.

 

[turbo]

The lack of mainstream support for intrinsic redshift is not proof of anything. The mainstream has been known to be wrong in the past.

You are right. In fact, the mainstream has been wrong many, many times in the past. This is the textbook definition of "paradigm shift", and that has happened often in physics. Unfortunately, this particular shift would be astronomically huge, so the stakes are very high.

Intrinsic redshift would, however, draw a great deal of attention if compelling evidence were found. It would obviously be a very mysterious phenomenon given current knowledge and scientists love a good mystery [not to mention the nobels for solving them]. The most reasonable explanation is the evidence for intrinsic redshift is not compelling.

There is plenty of evidence, but these observations are dismissed one-by-one as flukes and chance alignments. Taken together, they are compelling; however, the mainstream of physics has an even more compelling reason not to even consider that there might be cases where objects can have intrinsic redshift unrelated to cosmological expansion: There are millions of man-hours and billions of dollars that have been dedicated to projects supporting a cosmology that is predicated on the notion that redshift is caused by cosmological expansion. Hubble himself did not subscribe to this notion, by the way, although the "constant" is named for him. If the distance/redshift relationship is not the result of cosmological expansion, then extrapolating back to a Big Bang is nonsensical, and standard cosmology is seriously in error. You will not find many conventional astronomers who wish to give up their funded research projects and start over with a steady state model, although they will happily apply epicycles to keep the BB model patched up and reasonably predictive. This is not a conspiracy, nor is it evil, however it is human nature to protect one's turf, and anybody with a vested interest in SBB (professional, financial, personal...) will naturally look askance at even a hint that the Hubble relationship is not due to cosmological expansion.

This is why I was so surprised to see the SDSS site list this as an interacting galactic system. This particular example, the NGC 7603 system, has been roundly denounced by mainstream cosmologists as an "impossible" example of interaction because of the difference in redshifts. Just look at the SDSS image, though. It is obvious that the two major components are connected, and it doesn't take much of a leap to conclude that the embedded high-z objects may not be "chance projections", as well. Mainstream cosmologists somehow feel that it is OK to ignore observations that do not agree with the standard model, though, and this is wrong in so many ways.

 

[ohwilleke]

An argument for intrinsic redshift is particular interesting to the extent that it applies only to one class of objects (quasars) or perhaps a few others (such as tighly clustered galaxies), because it does not call into question the more general Cepheid and Ia supernova measurements which have independent corroboration. It simply suggests that one small class of objects, which were outlier data to start with, are at different distances than existing models would predict. Unlike Cepheids and Ia supernovas we don't have, e.g., good calibrating data on what a quasar should look like up close.

This doesn't have to have a huge amount of impact on Hubble's constant, because Hubble's constant data flow from a variety of redshifted objects.

This does significantly change how we look at the early evolution of the universe, because quasars are the dominant very high redshift objects. It is entirely possible that mainstream astronomy could be dead wrong about quasars, yet generally right about many things. Indeed the very name "quasi-stellar objects" implies the uncertainty regarding what quasars are, because if they really are as distant as they seem they have to be so damn bright for us to seem them as brightly as we do, while if they a closer, they can have much more reasonable brightness levels accompanied by intrinsic redshift.

Rightly or wrongly, I think one of the reasons that Arp has not been taken seriously on intrinsic redshift, where his data is relatively strong, is because he has had too much baggage of other theories with weak support that cause ad hominem distrust of his arguments. He is a strong proponent of quasi-steady state cosmology, which is hardly a necessary consequence of intrinsic redshift of certain classes of objects, and has at times also backed quite weird theories like the notion that mass is not constant over time. Also, his statistical arguments about quantized stellar and galactic scale phenomena have not held up well.

 

[Chronos]

Turbo-1, I think I understand and do respect your position. I suspect you are familiar with mine, as well. My problem with intrinsic redshift is the mechanism. All the physics we think we know cannot come up with a viable mechanism for intrinsic redshift. In fact, it would violate many aspects of particle physics that are held in very high regard. Observational evidence that does not fit theory is just as suspect as theoretical predictions that do not match observation

 

[turbo]

An argument for intrinsic redshift is particular interesting to the extent that it applies only to one class of objects (quasars) or perhaps a few others (such as tighly clustered galaxies), because it does not call into question the more general Cepheid and Ia supernova measurements which have independent corroboration. It simply suggests that one small class of objects, which were outlier data to start with, are at different distances than existing models would predict. Unlike Cepheids and Ia supernovas we don't have, e.g., good calibrating data on what a quasar should look like up close.

You are correct, of course, but calling into question the source of discordant excess redshift associated with quasars will let the camel's nose into the tent. The mechanism by which redshift arises will have to be looked at with some objectivity.

This doesn't have to have a huge amount of impact on Hubble's constant, because Hubble's constant data flow from a variety of redshifted objects.

I do not disagree that distant objects are more highly redshifted than close objects, in an apparently linear relationship. The Hubble relationship is non-controversial. Like Hubble, I am not convinced that the redshift is caused by cosmological recession. Light traverses apparently "empty" space that is in fact densely populated by the virtual particle pairs of the ZPE field - the ground state of the quantum vacuum. As EM waves propagate through this field, they may lose energy and become redshifted.

This does significantly change how we look at the early evolution of the universe, because quasars are the dominant very high redshift objects. It is entirely possible that mainstream astronomy could be dead wrong about quasars, yet generally right about many things. Indeed the very name "quasi-stellar objects" implies the uncertainty regarding what quasars are, because if they really are as distant as they seem they have to be so damn bright for us to seem them as brightly as we do, while if they a closer, they can have much more reasonable brightness levels accompanied by intrinsic redshift.

This is the most obvious paradox for quasars - how can an object smaller than our solar system emit energy equal to that of hundreds of galaxies? This is addressed in a very straightforward lesson format at the Chandra site: http://chandra-ed.harvard.edu/3c273/time_machine.html
Eliminating the excess redshift would allow us to place the quasars at reasonable distances and reduce their luminosities to more realistic levels.

Rightly or wrongly, I think one of the reasons that Arp has not been taken seriously on intrinsic redshift, where his data is relatively strong, is because he has had too much baggage of other theories with weak support that cause ad hominem distrust of his arguments. He is a strong proponent of quasi-steady state cosmology, which is hardly a necessary consequence of intrinsic redshift of certain classes of objects, and has at times also backed quite weird theories like the notion that mass is not constant over time. Also, his statistical arguments about quantized stellar and galactic scale phenomena have not held up well.

You have followed Arp pretty well, I see. He is an iconoclast, and as an observational astronomer, he does not express himself well in the language of the mathemeticians that rule the roost in cosmology. This leaves him open to dismissal as a crackpot, which is truly unfortunate, because he is/was one of the premiere observational astronomers of our time. His views regarding a quasi steady-state universe, while not mainstream, should never allow others to discount his observations. Indeed Fred Hoyle was marginalized by mainstream astronomers throughout much of his career for pursuing a similar cosmological model. If light can lose energy traversing large distances, and if the speed of light must remain constant in a vacuum, the energy loss will be evidenced by a reduction in frequency (redshifting). This is not an outrageous idea, and if it is true, we cannot extrapolate back to a Big Bang and a steady state universe model must be explored seriously.

 

[turbo]

Turbo-1, I think I understand and do respect your position. I suspect you are familiar with mine, as well. My problem with intrinsic redshift is the mechanism. All the physics we think we know cannot come up with a viable mechanism for intrinsic redshift. In fact, it would violate many aspects of particle physics that are held in very high regard.

Here is one mechanism that violates no known laws of physics, and is in fact to be expected. If light is being emitted from an object that is very close to a supermassive black hole, will the light not appear redshifted to us? There have been a number of papers about gravitational radiation recoil (kick) and slingshotting effects that can eject black holes from host galaxies, and we should expect to be able to detect some activity of this type. What would a black hole look like if it was ejected from a host galaxy and it stripped material from that galaxy along the way? I suspect that it might look very much like the NGC 7603/PGC 07041 system.

Observational evidence that does not fit theory is just as suspect as theoretical predictions that do not match observation

Observational evidence is not suspect - it is all we have. What should be suspect is the inappropriate interpretation of observational evidence.

 

[Chronos]

The arguments for redshift = expansion are pretty powerful. Tired light has a lot of baggage and fails to explain a number of observations that are readily explained by expansion - examples

There is only one known solution to the Einstein field equations that results in a static universe. This particular solution [which was found by de Sitter] interestingly enough produces the 'de Sitter effect' where both redshift and time dilation effects appear as a function of distance. The predicted effect is, however, exponential, not linear. The model was abandoned in the early 30's by researchers [including de Sitter] due to numerous conflicting observations.

There is no known way to decrease a photon's energy without scattering, save for gravity or doppler type effects [e.g., expansion], which can only produce redshifts in the range z<1. Any other known mechanism would cause objects to appear increasingly fuzzy with distance, which is not observed.

Tired light cannot explain the time dilation observed in the light curves of type Ia supernova, which correlates very closely to their redshift. See:
Timescale Stretch Parameterization of Type Ia Supernova B-band Light Curves
http://arxiv.org/abs/astro-ph/0104382

Tired light cannot explain the increase in temperature of the CMB measured at large redshifts. See:
The microwave background temperature at the redshift of 2.33771
http://arxiv.org/abs/astro-ph/0012222

Tired light does not explain the correlation between the observed surface brightness of galaxies and that predicted to occur as a result of expansion [redshift] by the Tolman surface brightness effect. See
A Tolman Surface Brightness Test for Universal Expansion...
http://arxiv.org/abs/astro-ph/9511061

Tired light cannot explain the perfect Planckian shape of the CMB blackbody spectrum. That shape remains Planckian only if the photons density decreases over time due to expansion. The CMB cannot be radiation from ancient stars. The spectrum shape would deviate widely from a true blackbody spectrum.

 

[turbo]

The arguments for redshift = expansion are pretty powerful. Tired light has a lot of baggage and fails to explain a number of observations that are readily explained by expansion - examples [snip]There is no known way to decrease a photon's energy without scattering, save for gravity or doppler type effects [e.g., expansion], which can only produce redshifts in the range z<1. Any other known mechanism would cause objects to appear increasingly fuzzy with distance, which is not observed.

So you agree that the gravitational effect (due to light being emitted from bodies in deep gravitational wells, for instance) can result in redshift without causing scattering/diffusion? Thank you! Here is a non-cosmological mechanism for observed redshift that can explain the excess redshift of quasars.

 

[Chronos]

So you agree that the gravitational effect (due to light being emitted from bodies in deep gravitational wells, for instance) can result in redshift without causing scattering/diffusion? Thank you! Here is a non-cosmological mechanism for observed redshift that can explain the excess redshift of quasars.

Yes, however this not enough explain redshifts of z>1. Another problem is that only a tiny percentage of photons would exhibit appreciable gravitational redshifts. The great majority of photons are emitted at large distances from the central black hole. The gravitational redshift of these photons would be negligible. Here, however, is the real test. Find an apparently interactive galaxy-quasar pair with disparate redshifts. Check for lyman forest absorption lines in both objects. If the absorption lines are identical and have the same redshift in both objects, you have a contender for non-cosmological redshift.

 

[turbo]

Yes, however this not enough explain redshifts of z>1.

How can this be, Chronos? Photons emitted near a black hole can be redshifted out of the visual range, and photons emitted near or at the event horizon can be redshifted completely out of EM detectability. What is the mechanism by which z>1 gravitational redshifts are forbidden?

 

[Chronos]

I'll take full credit for misstating the case on that count, Turbo-1. Indeed, photons emitted near enough to the schwazchild radius could have unlimited redshift. The more important issue is they are so few in number compared to the those being emitted at distances where gravitational redshift is not a factor, the effect is neglibigle. This assumes the quasar is powered by a central black hole and fueled by infalling matter. As matter accelerates toward the black hole it rapidly heats up enough to emit gamma rays. This occurs well before the infalling matter gets near enough to the schwarzchild radius to suffer any significant gravitational redshift. Were this not true, the spectrum of light emitted by matter spiraling into any black hole would be heavily redshifted regardless of distance. This is not observed. Plenty of black hole candidates have been found in this galaxy, including the monster in the center. Infalling matter does not exhibit any unexpected redshift.

 

[turbo]

OK, now for a thought experiment. If a black hole is "kicked" out of a galaxy by gravitational radiation recoil or a slingshot effect, it may emerge from the galaxy in a relatively "naked" state. Light emitted from its immediate environs will be heavily redshifted. As the black hole gathers matter from the intergalactic medium and forms a larger and larger accretion disk, the light that we see from that disk will be emitted from matter farther and farther away from the event horizon, and the apparent redshift of the object will decrease.

If you have read much of Arp's work, you will recall that he models quasars as ejection phenomenae that have initially high redshifts. Those redshifts moderate with age - he observes that quasars with greater angular separation from the ejecting galaxy have lower redshifts than quasars closer to the host. Here is a very simple non-technical model for variable non-cosmological redshift in quasars that is consistent with well-established classical physics.

 

[Chronos]

My objection is there are far too many highly redshifted quasars that have no apparent interactions with line of sight galaxies for that explanation to be satisfactory. If quasars are ejection events, and relatively dim compared to their mother galaxy, shouldn't there be an apparent companion nearby in all cases?

 

[turbo]

Well, given the vastness of space, and the fact that quasars may have very large intrinsic redshifts, it might be difficult to identify a host galaxy for each quasar. Furthermore, if the black hole is ejected out of a galaxy and it pulls relatively little matter with it, it may not become visible to us until it passes into a region with plentiful dust and/or gas, so it can develop an accretion disk.

Aside from this, if you will pull out a copy of Arp's first book "Quasars, Redshifts and Controversies", you will see that he made an effort to identify quasars with respect to likely hosts. These efforts were scorned by traditionalists as "projection effects" since the quasars were redshifted with respect to the host galaxies and were "obviously" not near those galaxies.

 

[turbo]

My objection is there are far too many highly redshifted quasars that have no apparent interactions with line of sight galaxies for that explanation to be satisfactory. If quasars are ejection events, and relatively dim compared to their mother galaxy, shouldn't there be an apparent companion nearby in all cases?

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/vlt/images/Top20/Top20/top4.html

If you have a VERY fast connection, you may wish to download the full TIFF version (78Megs). It is very detailed and beautiful.

 

[Nereid]

gravitational redshift observed; naked BH would be how bright?

I think you'll find turbo-1 that for a 'naked' BH, ejected from a galaxy, to be visible as a highly redshifted object due to its deep gravitational well, it couldn't possibly have the kind of absorption and emission line spectum that most quasars are observed to have (or at least if it did, that state of affairs certainly wouldn't be more or less unchanged for a decade or three). At least, not without introducing some wildly new physics.

First, how close to the event horizon would a clump of gas be to have a gravitational redshift of z = 1 (say)? Next, how massive would the BH have to be for that gas to be able to remain in a more-or-less stable configuration (think of all the mechanisms which would tend to disrupt the clump)? Finally, work out a realistic configuration of BH, gas, (whatever) that gives rise to a single observed gravitational redshift ... and no non-gravitational redshift!

For an idea of how extraordinary the environments are in which gravitational redshift has been observed ... AFAIK, only the intensely hot, inner regions of accretion disks, around SMBHs ... and even there the redshift shows up only in the (X-ray) line profile.

 

[Chronos]

Spectral classifications preclude gravitational redshift as a factor in AGN studies.

 

[turbo]

I think you'll find turbo-1 that for a 'naked' BH, ejected from a galaxy, to be visible as a highly redshifted object due to its deep gravitational well, it couldn't possibly have the kind of absorption and emission line spectum that most quasars are observed to have (or at least if it did, that state of affairs certainly wouldn't be more or less unchanged for a decade or three). At least, not without introducing some wildly new physics.

We may come to a more accurate understanding of quasars soon. These puzzles are hardly as problematic as the current consensus view of quasars, which can pack the luminosity of 100 large galaxies into the volume smaller than the diameter of our solar system. The wildly new physics required to perform that feat is somehow uncontroversial in standard cosmology.

Finally, work out a realistic configuration of BH, gas, (whatever) that gives rise to a single observed gravitational redshift ... and no non-gravitational redshift!

Why would you insist on seeing no non-gravitational redshift? Every astronomical observation involves redshifts due to the Hubble relationship, proper motion, etc. I would think that gravitational redshift would be pretty non-controversial to a BB fan. It is, after all, one of the classic tests of GR. The redshift of EM emitted near the event horizon of a BH is practically infinite, so we should not be surprised to find light emitted near a BH to be redshifted.

For an idea of how extraordinary the environments are in which gravitational redshift has been observed ... AFAIK, only the intensely hot, inner regions of accretion disks, around SMBHs ... and even there the redshift shows up only in the (X-ray) line profile.

We can easily measure the gravitational redshift of a white dwarf orbiting another star (like Sirius), and all the EM wavelenghts are shifted, not just X-rays. Should we expect that black holes can break these rules, somehow?

 

[Chronos]

We may come to a more accurate understanding of quasars soon. These puzzles are hardly as problematic as the current consensus view of quasars, which can pack the luminosity of 100 large galaxies into the volume smaller than the diameter of our solar system. The wildly new physics required to perform that feat is somehow uncontroversial in standard cosmology.

Really? What present physics fail to account for that?

Why would you insist on seeing no non-gravitational redshift? Every astronomical observation involves redshifts due to the Hubble relationship, proper motion, etc. I would think that gravitational redshift would be pretty non-controversial to a BB fan. It is, after all, one of the classic tests of GR. The redshift of EM emitted near the event horizon of a BH is practically infinite, so we should not be surprised to find light emitted near a BH to be redshifted.

The number of photons that escape close to the event horizon are trivial compared to the number emitted by infalling matter far distant from there. That argument falls apart under its own weight. All black hole powered emitters would show the same kink of redshift were that true.

We can easily measure the gravitational redshift of a white dwarf orbiting another star (like Sirius), and all the EM wavelenghts are shifted, not just X-rays. Should we expect that black holes can break these rules, somehow?

Irrelevant.

 

[Nereid]

We can easily measure the gravitational redshift of a white dwarf orbiting another star (like Sirius), and all the EM wavelenghts are shifted, not just X-rays.

Do you have a reference please turbo-1? I think this would be interest to quite a few PF members and guests.

 

[turbo]

Do you have a reference please turbo-1? I think this would be interest to quite a few PF members and guests.

I'd be pleased to provide references, some quite non-technical, some more Nereid/Chronos-friendly. Show me the math!

http://www.accessscience.com/Encyclopedia/2/29/Est_299050_frameset.html?doi
http://physics.njit.edu/~dgary/202/Lecture20.html
http://www.journals.uchicago.edu/ApJ/journal/issues/ApJ/v497n2/36707/sc3.html

And here is a historical overview outlining the earliest attempts:

http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?bibcode=1980QJRAS..21..246H

 

[Chronos]

This quote from one of the referenced articles sums it up..."For Sirius B, best measurement is Dl / l ~ 0.03% compared to theoretically exact value 0.028%." That falls a bit short of what you need to account for the z+1 models. But that is easy to explain. The z+1 models fall flat on their face unless you are proposing a gravitational constant that varies with time.

 

[Garth]

Surely nobody is questioning the observation of gravitational red shift? What is at issue is what proportion of a quasar’s red shift is gravitational and what is cosmological. If most of it is local gravitational red shift then you would expect the spectral lines to be smeared out with absorption lines of similar red shifts, coming from different regions of the accretion disc at different depths in the potential well.

What you actually see is typically a main spectrum at a large red shift with little smearing together with a Lyman Alpha forests at much less red shifts. This is consistent with a cosmological red shift with nearer absorption from intervening IGM clouds.

Garth

 

[turbo]

This quote from one of the referenced articles sums it up..."For Sirius B, best measurement is Dl / l ~ 0.03% compared to theoretically exact value 0.028%." That falls a bit short of what you need to account for the z+1 models. But that is easy to explain. The z+1 models fall flat on their face unless you are proposing a gravitational constant that varies with time.

I cited these measurements of white dwarf gravitational redshifts as a response to Nereid's comment:

For an idea of how extraordinary the environments are in which gravitational redshift has been observed ... AFAIK, only the intensely hot, inner regions of accretion disks, around SMBHs ... and even there the redshift shows up only in the (X-ray) line profile.

My point was that gravitational redshifts are well-known and uncontroversial, and the effects should not be expected to be confined to the X-ray line profile. White dwarfs are dense, yes, but nowhere near the density of the (seriously degenerate!) neutron stars, much less that of black holes. Again, black holes have infinite redshift at the event horizon. If a black hole is ejected (kicked) from a galaxy in a relatively naked state and then begins accreting matter from the IGM, very early in its career its accretion zone will be small, and close to the event horizon, and as it gathers more matter, the accretion zone will be larger and farther from the event horizon, where light will be less red-shifted. This does not involve variable gravity or variable mass.

High-mass, high-luminosity quasars are very common at high redshifts, and trend downward in apparent size as redshifts decrease. If quasars are a class of objects with similar qualities, we might reasonably expect to see a mix of larger and smaller quasars at all redshifts, however this is not the case. It is reasonable to ponder if the overstatement cosmological distance due to excess redshifts in faint quasars leads us to overestimate their masses.

Prediction: When the Large Binocular Telescope and other huge adaptive-optics instruments come on-line, fainter and fainter quasars with larger and larger redshifts (and larger and larger calculated masses) will be discovered, and the heirarchical model will encounter serious problems.

 

[Garth]

If quasars are ejected from galaxy cores, then presumably we should see a lot of blue shifted ones?

Garth

 

[Nereid]

High-mass, high-luminosity quasars are very common at high redshifts, and trend downward in apparent size as redshifts decrease.

Are you sure? Aren't they only 'high-mass, high-luminosity' in models which place them at cosmological distances?

Also, what are you referring to when you say 'trend downward in apparent size'? AFAIK, in all cases where a quasar has been resolved (at least in the optical), it turns out to be just where you'd expect the nucleus of the galaxy it apparently is in!

If quasars are a class of objects with similar qualities, we might reasonably expect to see a mix of larger and smaller quasars at all redshifts, however this is not the case.

Well, the data on the quasar luminosity function (assuming their observed redshifts are cosmological) is "... consistent with quasar models in which evolution is caused by the progressive exhaustion of the fuel supply to the central black hole. Quasars fade from an initial bright phase until a low, quasi-steady rate of energy production is reached. This rate declines only slowly over a long timescale. Quasars in this final phase of evolution are equivalent to local Seyfert galaxies." (http://www.journals.uchicago.edu/ApJ/journal/issues/ApJ/v513n1/38100/sc5.html ). I note in passing that these models are a better fit to the data than the PLE (pure luminosity evolution) models that I've talked about elsewhere.

 

[turbo]

If quasars are ejected from galaxy cores, then presumably we should see a lot of blue shifted ones?

Garth

Not unless the ejection velocity is high enough to overcome the cosmological AND intrinsic (if any) redshifts. That's asking a lot. A high-speed ejection event aimed in our direction would result in us measuring a redshift that is just not as high as we might otherwise see. The proper motion of the quasar would not result in an absolute blueshift, just relatively less redshift than we would observe if the object had been ejected in another direction.

 

[Nereid]

What is at issue is what proportion of a quasar’s red shift is gravitational and what is cosmological. If most of it is local gravitational red shift then you would expect the spectral lines to be smeared out with absorption lines of similar red shifts, coming from different regions of the accretion disc at different depths in the potential well.

What you actually see is typically a main spectrum at a large red shift with little smearing together with a Lyman Alpha forests at much less red shifts. This is consistent with a cosmological red shift with nearer absorption from intervening IGM clouds.

Don't forget the intensity of disk, emission mechanisms, timescales, etc!

turbo-1, do you have any references to papers which propose models of quasars as 'local' BH? I mean, ones which seriously try to work through the details of what the accretion disk is, how it's (kept) fed, and how EM emerges to look just like a quasar, when seen from 1 kpc to 10 Mpc?

I'm particularly interested in how gas clouds can have decades-long (at least) lifetimes sufficiently close to the BH to give the Lyman forest, yet far enough away to retain not only their distinct existence, but also their cool (the clouds are clearly discrete, and clearly have little in the way of internal turbulence, temperature variation, etc).

 

[turbo]

Are you sure? Aren't they only 'high-mass, high-luminosity' in models which place them at cosmological distances?.

Yes, that is exactly the case. The mass/distance function only shows up when they are placed at the cosmological distances dictated by their redshifts using the Hubble law.

Also, what are you referring to when you say 'trend downward in apparent size'? AFAIK, in all cases where a quasar has been resolved (at least in the optical), it turns out to be just where you'd expect the nucleus of the galaxy it apparently is in!

I probably should have said "mass" not size, referring to the mass/luminosity function in relation to redshift. Of course spectroscopy can be tough, and it's my understanding that many quasar candidates that have been found with radio telescopes but have not been optically identified because their optical component is dim. Is this because the accretion zone is as-yet undeveloped? Is it because, in accordance with the standard model, the quasar and its "fuzz" are too far away to be viewed in the optical? This may pose a problem, because it would lead to an apparent surplus of radio-loud quasars in the "distant and faint" group. Selection effects (radio vs visual) and the lack of an all-sky survey may lead to statistical glitches, here.

Well, the data on the quasar luminosity function (assuming their observed redshifts are cosmological) is "... consistent with quasar models in which evolution is caused by the progressive exhaustion of the fuel supply to the central black hole. Quasars fade from an initial bright phase until a low, quasi-steady rate of energy production is reached. This rate declines only slowly over a long timescale. Quasars in this final phase of evolution are equivalent to local Seyfert galaxies." ([URL=source[/URL]). I note in passing that these models are a better fit to the data than the PLE (pure luminosity evolution) models that I've talked about elsewhere.[/QUOTE]You may be right about the fit. If new large telescopes keep finding quasars with higher and higher redshifts, we're going to have a hard time keeping any heirarchical model tenable in the framework of a universe that is only 13.7Gy old.

 

[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.