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trinitree88
2013-Aug-30, 03:45 PM
Quasars sometimes occur in pairs. 650 such pairs are used by these authors to measure their environments. A remarkable result is noticed. SEE:http://arxiv.org/abs/1308.6222

Jerry
2013-Sep-03, 04:24 AM
It is good to see Jason is still at it - trying to detect the impossible at impossible distances.

I am also trying to remember if the transverse proximity effect has been verified in other quasar studies.


we do find excess HI Lyα absorption but it is roughly centered on z fg and it spans several hundred km/s to both positive and negative velocities.
What does he mean by z(fg)? The text implies it is in the wrong place to be associated with the foreground quasar, but what is z fg?

trinitree88
2013-Sep-03, 09:16 PM
It is good to see Jason is still at it - trying to detect the impossible at impossible distances.

I am also trying to remember if the transverse proximity effect has been verified in other quasar studies.


What does he mean by z(fg)? The text implies it is in the wrong place to be associated with the foreground quasar, but what is z fg?

Jerry. I believe he uses the f/g notation for foreground quasar and b/g notation for background quasar , and I'm assuming z fg is new shorthand for redshift of the foreground quasar..... pete

Jerry
2013-Sep-05, 08:18 AM
That is simple enough. So why would the foreground quasar be in at a different redshift than the proximity effect of the foreground quasar on the background event? If this proves to be the rule, rather than the exception, it would also strongly imply that at least a portion of the redshift is intrinsic. There is no way that the spectral interference of a foreground quasar should be at a disparagent redshift from the interfering quasar.

antoniseb
2013-Sep-05, 11:47 AM
That is simple enough. So why would the foreground quasar be in at a different redshift than the proximity effect of the foreground quasar on the background event? If this proves to be the rule, rather than the exception, it would also strongly imply that at least a portion of the redshift is intrinsic. There is no way that the spectral interference of a foreground quasar should be at a disparagent redshift from the interfering quasar.

I went through this 38 page paper and didn't see anything in which there was more than a 100 km/sec difference in red shift between the foreground quasar itself and the absorption through the proximity, which can largely be explained by the environment that the light of the quasar comes from. Did you see something with a bigger difference than that? I didn't read every word, except the graph captions, and conclusions.

Jerry
2013-Sep-05, 11:55 PM
I went through this 38 page paper and didn't see anything in which there was more than a 100 km/sec difference in red shift between the foreground quasar itself and the absorption through the proximity, which can largely be explained by the environment that the light of the quasar comes from. Did you see something with a bigger difference than that? I didn't read every word, except the graph captions, and conclusions.
It is complicated. As I understand it, he is widening the window inward ~100 km to allow for the intergalactic medium scatter - this is the F(2000) scaling. The wavelength shift is at the top of the graphs (W^2000); and here the peak redshifts somewhere nearer 2000 km/s. They allow a 1000 km/s distribution about the foreground quasar location, so there is little significance in the 'incoming' spectral shift.

In the search of individual quasars, they open the velocity distribution of the foreground quasar to 1500 km/s to allow for uncertainty in the foreground redshift; and 520 pairs quasars were analyzed. ((!) Nothing easy about this type of study).

Ok, here it is:

"We do find excess HI Ly (alpha) absorption but it is roughly centered on the z [shift of the foreground galaxy] and it spans several hundred km/s to both positive and negative velocities." So I am either reading something wrong in the first graph, or it the velocity is expressed in absolute values.

The main point in the paper is that the predicted transverse proximity effect - 'lighting up' the passing photon stream; is in fact just the opposite: The presence of strongly spectral adsorption. The authors conclude that this is impossible to understand, unless it is assumed the 'quasar on' light situation is short-lived; so that when the background photons transited the foreground quasar, the vicinity of the quasar was optically thick, and the quasar was not 'quasing'. They go on to say there are other possibilities, such as that the medium is so thick that it overwhelms the proximity effect.

Is it worth speculating that the hydrogen envelope is so thick, dark matter is not even needed?

Jerry
2013-Sep-07, 06:16 AM
http://arxiv.org/abs/1309.0814 The OBSCURED FRACTION OF AGN IN THE XMM-COSMOS SURVEY: A SPECTRAL ENERGY DISTRIBUTION PERSPECTIVE

This is a very important paper. Tracing Quasars and AGN counts into the cosmic past has for decades been one of the best evidences of cosmic evolution. Locally, the population has appeared dominated by broad-lined spectra, but with increasing distance, the narrow-lined event became more common and it seemed very clear that as quasars aged, they muddied up their environment. But once again, selection effects have been raising their ugly heads.

It now appears AGN are shrouded in a torus band of dust. The dust is much thicker, and more widely distributed than ever imagined. If you look down the barrel of an AGN, the spectra is quite clean, narrow lines with fairly clean spectra. Looking from the side, radiation transfer effects broaden the spectral lines, putting a bend in the spectrum below the powerful X-rays where absorption begins, and a bump in the spectrum in the IR.

It is the spectral signature that ages, not the population.

Wow.

Shaula
2013-Sep-07, 06:29 AM
It now appears AGN are shrouded in a torus band of dust. The dust is much thicker, and more widely distributed than ever imagined. If you look down the barrel of an AGN, the spectra is quite clean, narrow lines with fairly clean spectra. Looking from the side, radiation transfer effects broaden the spectral lines, putting a bend in the spectrum below the powerful X-rays where absorption begins, and a bump in the spectrum in the IR.
What is new about this? I was taught that as part of the unified model of AGN back in the late 90s! Looking at the paper all I see is a refining of that model. Not really a wow moment, more like better constraints on existing models.

Jerry
2013-Sep-09, 09:28 PM
What is new about this? I was taught that as part of the unified model of AGN back in the late 90s! Looking at the paper all I see is a refining of that model. Not really a wow moment, more like better constraints on existing models.
What the new constraints are demonstrating is that the earlier estimates of the type I/type II ratios underestimated the type II population:


Inherent in all of these demographic studies are ambiguities in how Type-1/2 AGN are identified and defined, and therefore their selection of AGN could be biased... For example X–ray surveys could be missing Compton thick Type-2 AGN, mid-IR selection could be severely contaminated
by star-forming galaxies, and optical Type-2 AGN surveys might be missing sources lacking strong narrow line emission.

Sorting out the biases is not easy, and it is further complicated by the fact more luminous AGN have wider torus openings, making it easy to over-estimate the type I/type II ratios in any flux-limited sample.


X–ray demography-based studies found an obscured fraction lower by a factor ∼ 2 in the optically thin regime, and by a factor of ∼1.3 in the thick one. We argue that X–ray studies miss a large fraction of the highly obscured-Compton-thick AGN...
...We do not find any clear evidence of evolution with redshift of the mid-infrared to bolometric luminosity ratio, and hence of the obscured fraction, as a function of both
L bol and L[2−10]keV.
Again, an estimated change with redshift of quasar ratios has been one of the strongest and most persistent evidences of cosmic evolution. Without it, the high metallicity measured in the most distant events (and running counter to evolutionary physics) should be a more heavily weighted parametric.

Reality Check
2013-Sep-09, 10:49 PM
Without it, the high metallicity measured in the most distant events (and running counter to evolutionary physics) should be a more heavily weighted parametric.
Hi Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics"?

The Obscured Fraction of AGN in the XMM-COSMOS Survey: A Spectral Energy Distribution Perspective (http://arxiv.org/abs/1309.0814) is an interesting paper but not groundbreaking as Shaula states. They are refining the existing AGN models by looking at the fraction of AGN that are obscured by dust.
What I find unexpected is that they found no evidence for evolution of obscured AGN with redshift in the X-ray region (soft/hard luminosity ratios). So the question becomes whether it is dust that is preventing us seeing the evolution, is the dust a symptom of the AGN stabilizing (not evolving) or is there some other cause.

Jerry
2013-Sep-11, 03:26 AM
Hi Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics"?Back in the sixties, we were taught the 'three legs' of evidence of an aging universe that started with a big bang: Hubble flow, the CMB, and the evolution (increasing metal content) in cosmic time. This third leg collapsed as each progressive view into the 'infant' universe revealed high iron content. Remember, back then, the most distant known galaxies were blue and low in heavy metal. It has been very obvious for very long that metallicity is no longer a supporting argument for Big Bang physics. However, many other trends such as AGN type ratios and the apparent decreasing number of AGN with increasing cosmic distance, currently provide overwhelming evidence of cosmic scale changes with distance:
The cosmic star formation history is found to be traced by the evolution of number density of Quasi-stellar objects So it seems.


The Obscured Fraction of AGN in the XMM-COSMOS Survey: A Spectral Energy Distribution Perspective (http://arxiv.org/abs/1309.0814) is an interesting paper but not groundbreaking as Shaula states. They are refining the existing AGN models by looking at the fraction of AGN that are obscured by dust.
What I find unexpected is that they found no evidence for evolution of obscured AGN with redshift in the X-ray region (soft/hard luminosity ratios). So the question becomes whether it is dust that is preventing us seeing the evolution, is the dust a symptom of the AGN stabilizing (not evolving) or is there some other cause.
Good point. I don't know whether these authors are trying to stress that some of the evolutionary trends need to be revisited, or if it is just a case of more beans with the same end result.

Reality Check
2013-Sep-11, 10:07 PM
...snipped everything except the answer to my question...
Which was, Jerry:

Hi Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics"?
You do know what a citation is Jerry :rolleyes:?



Good point. I don't know whether these authors are trying to stress that some of the evolutionary trends need to be revisited, or if it is just a case of more beans with the same end result.
The authors do not mention any need to "revisit" evolutionary trends so they are not stressing that at all. Their results merely point out that obscured AGN may be at an "evolutionary" plateau for some reason.

Jerry
2013-Sep-22, 05:55 PM
Which was, Jerry:

The authors do not mention any need to "revisit" evolutionary trends so they are not stressing that at all. Their results merely point out that obscured AGN may be at an "evolutionary" plateau for some reason.In my opinion, the absence of a transfer proximity effect; (if anything what is observed here, is quite the opposite) - is a sanity check upon our understanding of radiation transfer properties near AGN; and by extension, near most galaxies, not necessarily dusty ones. We don't know.

It is significant, because our interpretation of the integrated Sache-Wolf effect is largely based upon our understanding, or predictions of radiation transfer properties near galactic structures. While a lack of understanding in the visual spectrum does not necessarily extend into the microwave spectrum; it should give all of us reason to pause when we see precise calculations relating to the proportions of dark matter/dark energy derived from small peaks in the microwave background.

Shaula
2013-Sep-22, 06:35 PM
So your point is that because we don't necessarily get every detail of radiation transmission right in hugely complex environments like dusty AGN we should not claim to understand the far, far simpler case of the CMBR? Kind of like saying that because chaotic gravitational systems are horrendously hard to model accurately we should not trust pendulums...

Reality Check
2013-Sep-23, 02:53 AM
It is significant, because our interpretation of the integrated Sache-Wolf effect is largely based upon our understanding, or predictions of radiation transfer properties near galactic structures.
Is it significant that this statement seems ignorant about the integrated Sache-Wolfe effect (http://en.wikipedia.org/wiki/Sachs%E2%80%93Wolfe_effect#Integrated_Sachs.E2.80. 93Wolfe_effect), Jerry :)?
The Sache-Wolfe effect is caused by gravitational red-shift on the scales of super clusters and voids, not any "radiation transfer properties near galactic structures".

The concept is quite simple. Different densities of matter will cause different gravitational redshifts in the CMB. The Sache-Wolfe effect is basically split into three effects.
* non-integrated ("differences in the matter/energy density at the time of last scattering").
* integrated (relatively static gravitational wells and hills during the early universe)
* Late-time integrated (evolution of gravitational wells and hills)

P.S.

Hi Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics"?
First asked 2013-Sep-09.

Jerry
2013-Sep-25, 09:51 PM
Is it significant that this statement seems ignorant about the integrated Sache-Wolfe effect (http://en.wikipedia.org/wiki/Sachs%E2%80%93Wolfe_effect#Integrated_Sachs.E2.80. 93Wolfe_effect), Jerry :)?
The Sache-Wolfe effect is caused by gravitational red-shift on the scales of super clusters and voids, not any "radiation transfer properties near galactic structures".

The concept is quite simple. Different densities of matter will cause different gravitational redshifts in the CMB. The Sache-Wolfe effect is basically split into three effects.
* non-integrated ("differences in the matter/energy density at the time of last scattering").
* integrated (relatively static gravitational wells and hills during the early universe)
* Late-time integrated (evolution of gravitational wells and hills)

P.S.

First asked 2013-Sep-09.
As I said, it is an opinion. The integrated Satche Wolfe effect ASSUMEs there are no radiation transfer effects buggering up the microwave spectrum in the range assumed to be related to the early universe. My opinion is that we don't know enough about the microwave structure of our own solar system to make such lofty assumptions. Elaborating a little - we don't pretend to know which parts of the infrared background, Xray and Gamma Ray background are primortal - we can guess about local galaxy contributions. Why are we so sure that the microwave signature is effected by gravitational lensing, but not other radiative transfer effects near galactic structures? Should n't we be able to use the lensing effect to predict where other major structure will be found beyond the current radio or visual limits?

Shaula
2013-Sep-26, 06:20 AM
If it is an opinion not backed up by any science, even any back of the envelope calculations, why do you keep presenting it here?

Reality Check
2013-Sep-27, 12:29 AM
As I said, it is an opinion.

The physical fact is that something is causing the CMB to be red shifted and blue shifted in a pattern corresponding to super clusters and voids. Astronomers attribute that to gravitational red shift (integrated Sache-Wolfe effect).
If you can produce some evidence that some "radiation transfer effects" can actually cause the same effect then you should produce it, Jerry. Otherwise it is not an opinion - it is a fantasy :eek:.


Should n't we be able to use the lensing effect to predict where other major structure will be found beyond the current radio or visual limits?
Since there is no lensing effect in the integrated Sache-Wolfe effect (http://en.wikipedia.org/wiki/Sachs%E2%80%93Wolfe_effect#Integrated_Sachs.E2.80. 93Wolfe_effect), Jerry, it is fairly obvious that we cannot use it :D!

P.S.

Hi Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics"?
First asked 2013-Sep-09. 18 days and counting, Jerry!
This is beginning to look like another fantasy :D.

Jerry
2013-Oct-03, 08:37 PM
Hi Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics"?
First asked 2013-Sep-09. 18 days and counting, Jerry!
This is beginning to look like another fantasy :D.
Right of the press:

http://arxiv.org/pdf/1310.0684.pdf CHEMICAL CONSTRAINTS ON THE CONTRIBUTION OF POPULATION III STARS TO COSMIC REIONIZATION"
"Our work suggests that Population III stars probably do not resolve the tension between reionization constraints and the paucity of ionizing photons implied by
the observed population of star-forming galaxies at high redshift."

Reality Check
2013-Oct-08, 12:28 AM
Right of the press:

http://arxiv.org/pdf/1310.0684.pdf CHEMICAL CONSTRAINTS ON THE CONTRIBUTION OF POPULATION III STARS TO COSMIC REIONIZATION"
"Our work suggests that Population III stars probably do not resolve the tension between reionization constraints and the paucity of ionizing photons implied by
the observed population of star-forming galaxies at high redshift."
Which was published on 2 October 2013 - after your assertion, Jerry.
Thus the question remains:
Jerry, can you give some citations for this "high metallicity measured in the most distant events" and how it contradicts "evolutionary physics" that you asserted on 9 September 2013 (http://cosmoquest.org/forum/showthread.php?145963-Quasars-looking-at-quasars&p=2155292#post2155292)?
First asked 2013-Sep-09. 30 days and counting, Jerry!

Chemical constraints on the contribution of Population III stars to cosmic reionization (http://arxiv.org/abs/1310.0684v1) is interesting.
They use "evolutionary physics" ("a semi-analytic model of galaxy formation") to estimate the impact of Population III stars on reionization. They find that the model produced a duration of the Population III star era that would produce the observed metallicity of Population II stars but which could not account for the reionization.

antoniseb
2013-Oct-08, 02:08 PM
Which was published on 2 October 2013 - after your assertion, Jerry.
...
Hi Reality Check, this seems like both a violation of the be nice rule and kind of a strange bit of formalism being demanded. The whole area of discussion is something nearly the limit of our observational abilities, and there are papers being published on both sides of the issue. Jerry happens to have picked one side to promote, but there ARE papers predating his assertion supporting his argument. Are you saying there aren't? Are you demanding that for his to discuss this with you he needs to find specific citations? It seems like you're asking for more work than is necessary, since he supported his argument.

Reality Check
2013-Oct-08, 11:32 PM
I am saying that I do not know of any sources supporting his assertion and that he has not listed any of the sources that he based his assertion on.
As you point out, this is at the limit of our observational abilities and that alone would imply papers on both sides. I am not aware of literature on either side.

The "Chemical constraints on the contribution of Population III stars to cosmic reionization" pre-print does not seem to support the entire assertion since the model does produce the observed metallicity of Population II stars. The inability to account for reionization fits the contradicts evolutionary physics bit.
I was expecting something more along the lines of literature stating that "here are the observed metallicity of early galaxies and they do not fit models of the evolution of galaxies".

Jerry
2013-Oct-09, 05:37 PM
I am saying that I do not know of any sources supporting his assertion and that he has not listed any of the sources that he based his assertion on. It surprised me that I could not find a more concise source - when you study a topic for decades, your own conceptual verbiage doesn’t always embrace the current vernacular.

As you point out, this is at the limit of our observational abilities and that alone would imply papers on both sides. I am not aware of literature on either side.Interesting isn’t it? The consensus in the current cosmology is so strong, that discussion is generally confined to phrases like ’tension’ between the theory and the observations; or ‘poorly understood at this time’.

The "Chemical constraints on the contribution of Population III stars to cosmic reionization" pre-print does not seem to support the entire assertion since the model does produce the observed metallicity of Population II stars. The inability to account for reionization fits the contradicts evolutionary physics bit.
I was expecting something more along the lines of literature stating that "here are the observed metallicity of early galaxies and they do not fit models of the evolution of galaxies".The current debate is generally whether the re-ionization period and metal enhancement occurred in a observable timeframe.


Your are correct to ask ’what problem’ in the context of ‘WMAP cosmology‘; Hinshaws solution pushes the epic of Pop III stars beyond the observation horizon. (Which is how you sweep a problem under the rug.) . Kulkarni is arguing that since ionization is self damping, it could not have been completed so soon, and therefore there should be an evolutionary trail up to ~z=6; and predicts the evolutionary trend should be observable. Kulkarni is still looking for observational data which will support the theory.

In any case, the decades long search for evolving metal trends and Pop III stars, like the search for gravitational waves, has returned goose eggs. Some of us view that as a problem in cosmology that is poorly understood at this time.

Reality Check
2013-Oct-10, 01:41 AM
The current debate is generally whether the re-ionization period and metal enhancement occurred in a observable timeframe.

Is this what

Again, an estimated change with redshift of quasar ratios has been one of the strongest and most persistent evidences of cosmic evolution. Without it, the high metallicity measured in the most distant events (and running counter to evolutionary physics) should be a more heavily weighted parametric.
actually means, Jerry?
Without the context of the Chemical constraints on the contribution of Population III stars to cosmic reionization (http://arxiv.org/abs/1310.0684v1) pre-print or any other source, your statement sounds like the high metallicity is not matched in models.


Your are correct to ask ’what problem’ in the context of ‘WMAP cosmology‘; Hinshaws solution pushes the epic of Pop III stars beyond the observation horizon.

Whoops - citation needed, Jerry :). The pre-print does cite one paper by Hinshaw et al.
As you state Kulkarni gives an argument that extends the Population III era. Hinshaw gives another.
These are problems for the models of galaxy evolution.

There is no problem that I can see as far as 'WMAP cosmology' is concerned.
The existence of the Big Bang has overwhelming evidence (http://www.astro.ucla.edu/~wright/cosmology_faq.html#BBevidence). That means reionization happened.
We know that Population II stars exist. Thus there must have been an era of Population III stars to create the observed metallicity in the Population II stars (unless you have another explanation?).
If Population III stars are needed to fully explain reionization then they must have been around long enough to do this. There is tension between the galaxy formation models and the needed duration.

Jerry
2013-Oct-17, 04:12 PM
Is this what

actually means, Jerry?
Without the context of the Chemical constraints on the contribution of Population III stars to cosmic reionization (http://arxiv.org/abs/1310.0684v1) pre-print or any other source, your statement sounds like the high metallicity is not matched in models.


Whoops - citation needed, Jerry :). The pre-print does cite one paper by Hinshaw et al.
As you state Kulkarni gives an argument that extends the Population III era. Hinshaw gives another.
These are problems for the models of galaxy evolution.
Hinshaw paper:
http://arxiv.org/abs/astro-ph/0302217
You have to pull up the Bennett paper to, to put it all together:
http://arxiv.org/pdf/1212.5225v3.pdf

All of which is rather moot - The Planck data supersedes the WMAP; the tightly converging circles have been redrawn decreasing the Dark Energy Component and allowing some latitude in the reionization period. Frankly, as the search for Pop III features continued; it should be safe to imply many astrophysicists never thought the Pop III events should be pushed completely beyond the event horizon.


There is no problem that I can see as far as 'WMAP cosmology' is concerned.Look at the constraints in the Bennett and Hinshaw papers, and compare them with the Planck constraints. They do not overlap; and as others have pointed out, this is not a major concern - but it does mean the WMAP constraints were much too optimistic.



The existence of the Big Bang has overwhelming evidence (http://www.astro.ucla.edu/~wright/cosmology_faq.html#BBevidence). That means reionization happened.
We know that Population II stars exist. Thus there must have been an era of Population III stars to create the observed metallicity in the Population II stars (unless you have another explanation?).
If Population III stars are needed to fully explain reionization then they must have been around long enough to do this. There is tension between the galaxy formation models and the needed duration.
No. If the theory is correct; Pop III stars are needed to build the universe within the time constraints imposed by the theory. That is all. If there is never any observational evidence of the 'fast breeding' galaxies; it is the theory that takes a hit. That is why the searches for Pop III galaxies are well funded.

Many astrophysicists were frustrated when the WMAP results were announced; not only collating all the data and declaring a lambda victory; but so tightly constraining the parameters that 'we might as well all go home' - as one put it. Planck reset the bars.

If you look at Mr. Wright's cosmological evidence of the Big Bang; he uses four data sets of observational evidence that support ONLY a Big Bang sequence:

The CMB

Evolution in Radio/quasar populations

Evidence the CMB was warmer in the Past.

Lithium and other light metal ratios.

You could add a few things like BACs; but this and other oft-sited evidence has degeneracies. So of these four: You acknowledged there is a lithium problem; evidence of evolution in the radio/quasar population relies upon our understanding of quasar environments and radiation transfers near these sources. This study says our preconceptions were wrong. Removing foreground contamination in the CMB also requires a good understanding of radiation transfer near galaxies, especially galaxies with AGN.

Finally, if you look at supernova and gamma ray burst data - the distant sample is highly ambiguous, very very difficult to interpret at this time.

This is a time when prior theories need to be subjected to the utmost scrutiny. If the predictions are not holding, if the incoming observational data doesn't bare the predicted fruit - no transverse proximity effect, no gravitational waves, no Pop III observations; the wrong light metal ratios; the fundamental assumptions need to be revisited, not just tweaked.

Reality Check
2013-Oct-17, 11:35 PM
All of which is rather moot - The Planck data supersedes the WMAP; the tightly converging circles have been redrawn decreasing the Dark Energy Component and allowing some latitude in the reionization period. Frankly, as the search for Pop III features continued; it should be safe to imply many astrophysicists never thought the Pop III events should be pushed completely beyond the event horizon.

Frankly a citation linking the "Pop III features" to the WMAP/Planck data could be needed. Jerry :)!
The actual search for Pop III features would be from looking for Pop II stars, e.g. using the James Webb telescope.



No. If the theory is correct; Pop III stars are needed to build the universe within the time constraints imposed by the theory.

Not quite right, Jerry. If the observation and theory of reionization correct, something is needed to perform the reionization. The Pop II stars cannot explain all of the reionization. Astronomers think that Pop III stars can provide the rest of the ionizing radiation. That is a reason why the searches for Pop III galaxies are well funded.


If you look at Mr. Wright's cosmological evidence of the Big Bang; he uses four data sets of observational evidence that support ONLY a Big Bang sequence:

If you look at Professor Wright's cosmological evidence of the Big Bang; you see 5 observations that support a Big Bang model over a Steady State model, Jerry.
The existence of the Big Bang has overwhelming evidence. (http://www.astro.ucla.edu/~wright/cosmology_faq.html#BBevidence)


The observations listed above are consistent with the Big Bang or with the Steady State model, but many observations support the Big Bang over the Steady State:
•Radio source and quasar counts vs. flux. These show that the Universe has evolved.
•Existence of the blackbody CMB. This shows that the Universe has evolved from a dense, isothermal state.
•Variation of TCMB with redshift. This is a direct observation of the evolution of the Universe.
•Deuterium, 3He, 4He, and 7Li abundances. These light isotopes are all well fit by predicted reactions occurring in the First Three Minutes.
Finally, the angular power spectrum of the CMB anisotropy that does exist at the several parts per million level is consistent with a dark matter dominated Big Bang model that went through the inflationary scenario.

I know of the historical problem with the 7Li abundance - I do not know the current status.
"Radio source and quasar counts vs. flux" needs a fuller explanation on that web page but it looks to be basically about the counts of these galaxies and observed flux.
Source counts in the chronometric cosmology (http://adsabs.harvard.edu/full/1987ApJ...313..551W) by E.L. Wright (1987)

The chronometric cosmology (a static, homogeneous, and hence nonevolving model proposed by Segal) is unable to explain the steep number versus flux law N(S) for quasars or extragalactic radio sources. The explanation given by Segal to explain the steep N(S) laws gives at best a small increase over a Euclidean N(S) proportional to S exp-1.5, and requires that the source spectral index be close to but greater than zero to create the effect. For typical radio spectral indices of roughly 0.75, the chronometric model cannot give a quantitative fit to the excess number of 1-3 Jy sources that the standard cosmology attributes to evolution. Thus the chronometric model can explain a steep N(S) law only for flat spectrum sources, while the observations show the steepest N(S) law for steep spectrum sources. Furthermore, the observed N(S) law for ultraviolet excess quasars is steeper than the steepest possible chronometric prediction.


Removing foreground contamination in the CMB also requires a good understanding of radiation transfer near galaxies, especially galaxies with AGN.

Citations please, Jerry.
My understanding of the removal of foreground contamination in the CMB is it is based on a good understanding of the universe and quite well tested.


Finally, if you look at supernova and gamma ray burst data - the distant sample is highly ambiguous, very very difficult to interpret at this time.

What do you mean by "distant"?
Citations please, Jerry.

Reality Check
2013-Oct-17, 11:40 PM
First-Year Wilkinson Microwave Anisotropy Probe (WMAP)1 Observations: Foreground Emission (http://iopscience.iop.org/0067-0049/148/1/97/fulltext/57710.text.html)
C. L. Bennett et. al (2003)

The WMAP mission has mapped the full sky to determine the geometry, content, and evolution of the universe. Full-sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the cosmic microwave background (CMB) from foreground emission, including diffuse Galactic emission and Galactic and extragalactic point sources. We define masks that excise regions of high foreground emission, so CMB analyses can be carried out with minimal foreground contamination. We also present maps and spectra of the individual emission components, leading to an improved understanding of Galactic astrophysical processes. The effectiveness of template fits to remove foreground emission from the WMAP data is also examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We use a maximum entropy method to construct a model of the Galactic emission components. The observed total Galactic emission matches the model to less than 1%, and the individual model components are accurate to a few percent. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (βs ∼ -2.5) near star-forming regions, especially in the plane, and steepest (βs ∼ -3) in the halo. This is consistent with a picture of relativistic cosmic-ray electron generation in star-forming regions and diffusion and convection within the plane. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to βs < -3. The modeled thermal dust spectral index is also steep in the WMAP bands, with βd ≈ 2.2. Our model is driven to these conclusions by the low level of total foreground contamination at ∼60 GHz. Microwave and Hα measurements of the ionized gas agree well with one another at about the expected levels. Spinning dust emission is limited to ≲5% of the Ka-band foreground emission, assuming a thermal dust distribution with a cold neutral medium spectrum and a monotonically decreasing synchrotron spectrum. A catalog of 208 point sources is presented. The reliability of the catalog is 98%; i.e., we expect five of the 208 sources to be statistically spurious. The mean spectral index of the point sources is α ∼ 0 (β ∼ -2). Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0 ± 1.4) × 10-3 μK2 sr at Q band and negligible levels at V band and W band. The Sunyaev-Zeldovich effect is shown to be a negligible "contamination" to the maps.
So basically they do what I expect - exclude point sources such a AGN galaxies, remove the Milky Way contamination, etc. And test that any remains contamination is negligible.

Jerry
2013-Nov-03, 05:05 AM
First-Year Wilkinson Microwave Anisotropy Probe (WMAP)1 Observations: Foreground Emission (http://iopscience.iop.org/0067-0049/148/1/97/fulltext/57710.text.html)
C. L. Bennett et. al (2003)

So basically they do what I expect - exclude point sources such a AGN galaxies, remove the Milky Way contamination, etc. And test that any remains contamination is negligible.
Well, you better subtract out any solar contamination; also Jupiter has a hell of a microwave signature (WMAP used it for calibration purposes); and since the milky way looks just as milky in the microwave range as its does in the visual spectrum, isn't it a little silly to think that AGN can be subtracted out, and there are no more corrections needed for every other galaxy?

This paper http://arxiv.org/pdf/1310.6351.pdf provides a laundry list of galactic interference effects that can contaminate the background signature; and I don't care how big your motorboat is, if the lake is large and there are a lot of ducks on the pond, it takes only a few minutes for your wake to disappear amongst the quackers. Nine billion years and ninety billion galaxies later, how pristine is the background signature? Keep in mind, that when the background theory was proposed, nobody dreamed how many cosmic features are spewing microwaves. Nobody expected galaxies are peppered with magnetic fields and the spinning ferrous grains that we know are there today. Nobody predicted peaks in the infrared, gamma and Xray backgrounds, either; but they are there: blackbody-like peaks in at least four bandwidths.

And how do you really test for the purity of your results? There is no absolute cosmic standard being beamed out of hinderspace so that we can check our work. It is all rather blind supposition.

Reality Check
2013-Nov-04, 11:29 PM
Well, you better subtract out any solar contamination;
...snipped some irrelevant stuff...

So basically they do what I expect - exclude point sources such a AGN galaxies, remove the Milky Way contamination, point the instrument away from the Sun so it does not fry!, etc.
And test that any remains contamination is negligible:
First-Year Wilkinson Microwave Anisotropy Probe (WMAP)1 Observations: Foreground Emission (http://iopscience.iop.org/0067-0049/148/1/97/fulltext/57710.text.html)
C. L. Bennett et. al (2003)


isn't it a little silly to think that AGN can be subtracted out, and there are no more corrections needed for every other galaxy?
Isn't it a bit silly to think that astronomers do not know that they can subtract out strong microwave point sources (AGN galaxies) and that weak microwave point sources (other galaxies) contribute to the remaining negligible contamination?

Of course that demand leads to the rather silly position that the CMB analysis is useless until we have detected and corrected for every galaxy in the universe :).
The reality is a common experimental and analytical technique - correct for known background effects and the unknown background effects become experimental/analytical errors.