SDSS Quasars & Cosmology: Challenges to Current Models

[Nereid]

The offhandedness of your remark make its literal reading ridiculous Nereid. I expect better of you. Strauss made this comment rather forcefully in the presentation, and the 2002 paper that matt.o dug up reinforces it. Strauss points out that because MgII and FeII are formed and distributed by different kinds of SN events, some redshift-dependent evolution in the relative metallicities had been expect. None was found, nor was a redshift-dependent evolution in total metallicity found. This is a major point. It would be difficult to miss these points in Strauss' presentation.

Did you read Pentericci et al. 2002, AJ, 123, 2151?

Did you read my transcript of the Strauss video?

What one finds in the literature today are observations like those done by SDSS and others, with error bars, etc. (good science) and more speculative stuff. The more speculative papers say things like "z~6.5 quasars are massive and so mass must accrete faster than we have previously considered" and "z~6.5 quasars are highly metallized, so metals must be formed in some fashion that we have not previously considered".

Sadly, I have no more time to track down the relevant papers, so I'll simply note that your record of accuracy in this regard is less than stellar, turbo-1, and I would urge any reader interested in the current state of research to go read the relevant papers for themselves*.

These are statements of faith in BB cosmology, not science, because they rely on invocation of as-yet unknown processes by which these extreme objects might have been able to form.

You keep saying this, and I^ keep saying it is the very essence of good science.

Clearly, there is a stark disagreement.

Myself, I think the disagreement likely rests on a very big difference in perceptions of the nature of science, and the extent to which modern astrophysics and cosmology are sciences.

To get these two perceptions clearly on the table, and discussed, would likely be best done by continuing the thread https://www.physicsforums.com/showthread.php?t=170753"; would you care to continue there?

Astronomy is an observational science, and observing objects at the limits of detectability it a tricky business. Re-building cosmology based on a small sample of single-band detections at z~5.7 should be viewed as an exercise in speculation, IMO.

Not sure what you're saying here, turbo-1, would you please clarify?

Specifically, are you saying that observations of "a small sample of single-band detections at z~5.7" should not form any part of evidence for alternative cosmological theories (e.g. those positing a "spatially and temporally infinite universe")?

I hope to have a bit more uninterrupted time to devote to this thread. More later.

Sadly, I have no more such time.


* it's a big task; there are hundreds of them
^ and some others too

 

[Sundance]

Re: Laura Pentricci papers

I was in the middle of reading these papers when I saw your comments.

L.Pentericci
http://arxiv.org/find/all/1/all:+Pentericci/0/1/0/all/0/1

Maybe reading some of these papers may add light to the discussion.

 

[Nereid]

Nereid, your strength seems to be cross-examination, judging from numerous posts in this most illuminating thread. Since cosmology is a subject that in the absence of experimentation depends on ratiocination and analysis of circumstantial evidence, your stance as council for the defence of the current consensus is entirely appropriate. I, for one, certainly enjoy it.

[...]

Glad you are enjoying it, oldman.

Of course, it's not only cosmology*; that pretty much describes all of astrophysics too (and geology and paleontology and ...).

One thing I find curious, and frustrating, is the extent to which pseudo-science, and even anti-science, shows up here in PF, despite https://www.physicsforums.com/showthread.php?t=5374"^; another is just how poorly understood the actual work of cosmologists, astrophysicists, and astronomers is - look at the myriad of things PF posters seem to mean when they use the word "observation" for example, blithely unaware (for the most part) of just how steeped in physics theories these observations actually are.

* "a subject that in the absence of experimentation depends on ratiocination and analysis of circumstantial evidence"
^ "Poorly formulated personal theories, unfounded challenges of mainstream science, and overt crackpottery will not be tolerated anywhere on the site". While there are some examples of misunderstandings of cosmology, as a science, and perhaps one or two examples of pseudo-science, in this thread, it is not an example of anti-science.

 

[Nereid]

Re: Laura Pentricci papers

I was in the middle of reading these papers when I saw your comments.

L.Pentericci
http://arxiv.org/find/all/1/all:+Pentericci/0/1/0/all/0/1

Maybe reading some of these papers may add light to the discussion.

That was one of the first places I looked, Sundance, for "Pentericci et al. 2005 VLT near-IR spectra".

She has certainly (co-)written many interesting papers, but the one Strauss mentions in his video (and accompanying Supporting Material) is clearly not in the list in your link.

 

[Sundance]

What is the issue?

What is the point of discussion?

 

[turbo]

Myself, I think the disagreement likely rests on a very big difference in perceptions of the nature of science, and the extent to which modern astrophysics and cosmology are sciences.

To get these two perceptions clearly on the table, and discussed, would likely be best done by continuing the thread https://www.physicsforums.com/showthread.php?t=170753"; would you care to continue there?

No. Lieu and Disney make their cases in generalities, and I am not about to defend their opinions/points of view. I have made some very specific statements about Strauss' overview of the SDSS observations that pose severe constraints on our current models of metallicity and mass-formation, only to see them either nay-sayed or ignored or "addressed" with mainstream citations that don't address the problems appropriately.

Specifically, are you saying that observations of "a small sample of single-band detections at z~5.7" should not form any part of evidence for alternative cosmological theories (e.g. those positing a "spatially and temporally infinite universe")?

You know that I am NOT saying that - you are reading into my intentions and thoughts. Such observation must be taken into account, but the small sample size and the artificial constraint of z~6.5 (which corresponds to the limits of detection of the SDSS equipment through a single filter) makes the risk of errors due to selection effects a very real problem.

I have shown that our current view of stellar neucleosynthesis constrains the rate at which FeII can be formed, as it is the last and heaviest metal that can be formed through fusion. Sadly, no engagement on this count.
https://www.physicsforums.com/showpost.php?p=2019946&postcount=42

I have shown you that the formation of even z~6 quasar masses poses some severe problems in current cosmology. This was from a mainstream paper that you cited.
https://www.physicsforums.com/showpost.php?p=2019946&postcount=42

Sadly, I have no more time to track down the relevant papers, so I'll simply note that your record of accuracy in this regard is less than stellar, turbo-1, and I would urge any reader interested in the current state of research to go read the relevant papers for themselves*.

I encourage any interested readers to listen to the Strauss presentation in the OP. When (s)he gets to the part when he explains that there is no red-shift dependent evolution apparent in either absolute nor relative concentrations of MgII or FeII in these quasars, refer to Post 40, in which Neried denies that Strauss ever made such a statement. In fact, Strauss went on to say that there was no red-shift dependent evolution apparent in any of the metrics by which SDSS evaluated these quasars. Cherry-picking indeed. Color added for emphasis and comparison with my alleged "less than stellar record of accuracy."

and show no evolution with redshift - turbo-1

The brevity of this statement makes its literal reading ridiculous ... of the 19/20 z>5.7 quasars mentioned in the Strauss video, no comments about "evolution with redshift" were made. Presumably turbo-1 meant that AGNs show no evolution with redshift, over the range ~0.1 < z ~6.5. If so, to ask a single paper to explain this reported result AND the observed metallicity of ~20 z>5.7 quasars is a bit extreme (unless it were a review paper).

 

[turbo]

What is the issue?

What is the point of discussion?

Read the OP, Sundance and view Michael Strauss' presentation to the astronomers at the Space Telescope Science Institute.

 

[Sundance]

Re First post by Turbo

Scroll down to Nov 2, 2005 and watch Michael Strauss' presentation to the Space Telescope Science Institute. Strauss is the scientific spokesperson for the Sloan Digital Sky Survey, and has co-authored many ground-breaking papers. There are several points that he makes about quasars in this presentation that should give any loyal BB-adherent pause.

1) SDSS has observed quasars out to z~6.5. Because luminosity falls off as a function of the square of the distance (absent absorption), if quasars are at the distances implied by their redshifts, these distant quasars would have be be powered by black holes of several billion Solar masses, cannibalizing host galaxies of over a trillion Solar masses. Since z~6.5 corresponds to a time a few hundred million years after the BB, how did these monsters have time to form?

2) These high-z quasars have solar or super-solar metallicities. Our Sun is presumably the product of generations of supernovae, so how did these massive bodies get so metal-enriched so early?

3) Because elements are formed in stars through different processes, cosmologists expected to see some evolution in the metallicities of quasars with redshift. SDSS found none, even out to z~6.5, either in absolute or relative metallicity.

4) Cosmologists expected that higher-redshift quasars would stand a much higher chance of being lensed because of the very long distances and the increased chance of intervening massive objects on our line-of-sight to them. None of the z=5.7-6.5 quasars in the SDSS survey are lensed.

Re 1)

Some of these monster cluster,cluster of galaxies require over 50 billion yrs to form. That is the reality, now the dating process that has been used only dates from a specific phase and does not take into consideration transient phases, so we have dating of about 13 to 14 billion years even though some star are dated over 15 billion years. Not to mention 18 Billion Sun mass BH that has a life span of over 100 Gyrs.

Re 2) The phase changes that Stars go through alter the metallicity by photodisintegration in the early stages of supernova that enable to break down of eg Fe to He to H to Neutrons and through a property of magnetic entanglement are compacted and are collected by the core to sometimes form a Neutron star. The matter avialble would determine the extent of the Neutron star or composite or even the next transient phase of a formation of a black hole form that has entrapping horizons.
Metallicity in stars is a general explanation and you can google for the information.

Re 2) Quasars near and far have been found to have the same properties. There are varies forms of quasars large and small. The extreme large ones contain a monster black hole that forms main jets that can eject matter for millions of light years affecting not only the form of the lacal galaxies but also the form of distant galaxies. Its power can form dwarf galaxies that in time merge and form larger galaxies. Because they are located in the centre of clusters of galaxies we need to search far in order to find them. Think about it, where is the centre of the nearest cluster of cluster of galaxies?
The reality of it is that we can observe the workings of the nearest without the complicated observation of the far, where data can be in error from intrinisc properties. Our tools at the present time are limited.

Re 3) Monster Objects deep field give us a better understanding of lensing because we can see the overall affect. Within the next few years we hope to get a better understanding through better science.

The issue that comes to mind is that many scientists assume that the BBT is correct than proceed to fit the data to the model. Lately scientists have been applying science to the data and their comments are closer to reality in so to speak. One of the problems with the science comminity is that the main projects are directed to the BBT that is paid for by politics and churches. If you have alternative theories your on your own and best of luck.

The general theme is that galaxies near and far have similar properties and in many cases we are discovering new forms and new properties and why not, we are still discovering new species in rainforsts and in the depths of the oceans.

Well that's my opinion.

 

[Suede]

I like turbo.

Here is a guy that looks a data and takes it for what it is.

The process of fitting models to observations are what led to the creation of Ptolemy's epicycles.

Science MUST be backed by falsifiable experiments or its no better than myth.

 

[Chronos]

Taking data at face value is precisely what Ptolemy did. And in all fairness to Ptolemy, his 'epicycles' fit observational data remarkably well for many years. But, it was not the best [simplest] explanation in the long run. No model is immune to the relentless march of science. Even GR will eventually yield to scientific progress.

 

[Suede]

Even GR will eventually yield to scientific progress.

The sooner the better IMHO.

Speaking of falsifiable, anyone have a status on the LIGO's findings?

How about the CDMS project?

Gravity Probe B?

hmmm...


As for Ptolemy matching observational data, the end result is expected. When you match models to observation without conducting fasifiable experiments, it ceases to be science and instead becomes dogma.

 

[Nereid]

Evolution of metallicity in galaxies ...

Here's an interesting, recent paper* that has considerable relevance to some of the broader issues turbo-1 raises in this thread:

http://arxiv.org/abs/0806.2410" :

We present initial results of an ESO-VLT large programme (AMAZE) aimed at determining the evolution of the mass-metallicity relation at z>3 by means of deep near-IR spectroscopy. Gas metallicities are measured, for an initial sample of nine star forming galaxies at z~3.5, by means of optical nebular lines redshifted into the near-IR. Stellar masses are accurately determined by using Spitzer-IRAC data, which sample the rest-frame near-IR stellar light in these distant galaxies. When compared with previous surveys, the mass-metallicity relation inferred at z~3.5 shows an evolution much stronger than observed at lower redshifts. The evolution is prominent even in massive galaxies, indicating that z~3 is an epoch of major action in terms of star formation and metal enrichment also for massive systems. There are also indications that the metallicity evolution of low mass galaxies is stronger relative to high mass systems, an effect which can be considered the chemical version of the galaxy downsizing. The mass-metallicity relation observed at z~3.5 is difficult to reconcile with the predictions of some hierarchical evolutionary models. Such discrepancies suggest that at z>3 galaxies are assembled mostly with relatively un-evolved sub-units, i.e. small galaxies with low star formation efficiency. The bulk of the star formation and metallicity evolution probably occurs once small galaxies are already assembled into bigger systems.

At any given epoch, AGNs are rare objects, compared with galaxies.

Even today, I think it's true to say that AGNs are quite poorly understood, compared with galaxies^.

How galaxies evolve - in terms of their gas content, morphology, rate of star formation, etc, etc, etc - is a relatively recent topic in astrophysics.

Even more recent is high quality observations of high-z galaxies, which can be used to study various aspects of galaxy evolution (among other things).

Thus it's not unreasonable to expect that detailed understanding of how AGNs evolve will likely trail similar understanding of how galaxies evolve, though AGN evolution will certainly be informed by results obtained from studying galaxy evolution.

In any case, research into the formation of both AGNs and galaxies is highly constrained today by an almost complete lack of relevant observations ... about all we know is that it took place in the Dark Ages, between the surface of last scattering and the epoch of re-ionisation.

The introduction section of the Maiolino et al. paper is worth reading carefully; one gets a real sense of both excitement and of how little is yet firmly established.

The second two paras of the introduction are well worth quoting, as they illustrates well just how much, and how little, is known (plus how active a field of research this is):

Various physical processes may be responsible for the mass-metallicity relation. One possibility is that outflows, generated by starburst winds, eject metal-enriched gas into the IGM preferentially out of low-mass galaxies (due to the shallow gravitational potential well),making their enrichment less effective than in massive systems (e.g. Tremonti et al., 2004; De Lucia et al., 2004; Finlator & Dav´e, 2008). An alternative scenario is that low mass systems are still at an early evolutionary stage and have still to convert most of their gas into stars, hence they are poorly metal-enriched relative massive galaxies (which are instead already evolved). This is the so-called “galaxy downsizing” scenario, supported by various observational evidences (e.g. Juneau et al., 2005; Feulner et al., 2005; Franceschini et al., 2006; Asari et al., 2007; Perez-Gonzalez et al., 2007), where massive galaxies formed most of their stars rapidly and at high redshift, while low mass systems are characterized by a slower evolution, which extends to low redshift. Finally K¨oppen et al. (2007) ascribes the mass-metallicity relation to variations of the IMF high-mass cutoff in different star forming environments.

The relative role of these processes in shaping the mass-metallicity relation is debated. It is likely that each of them contributes at least to some extent, since observational evidences have been found for all of them. Each of these factors (outflows/feedback, downsizing, IMF) has profound implications on the evolution of galaxies. Therefore, it is clear that the mass-metallicity relation contains a wealth of information useful to constrain models of galaxy formation and evolution. Indeed, any model of galaxy evolution is now required to match the mass–metallicity relation observed locally (e.g. Kobayashi et al., 2007; Brooks et al., 2007; de Rossi et al., 2007; Dav´e & Oppenheimer, 2007; Dalcanton, 2007; De Lucia et al., 2004; Tissera et al., 2005; Bouch´e et al., 2006, 2007; K¨oppen et al., 2007; Cid Fernandes et al., 2007; Finlator & Dav´e, 2008; Tassis et al., 2008). However, different models predict different evolutionary patterns of the mass-metallicity relation as a function of redshift, and observational data are required to test and discriminate among them.

We surely live in (astrophysical) exciting times!

* actually a preprint, though is apparently "in press" (A&A)
^ with the exception of extreme dwarf galaxies

 

[matt.o]

Hot off the press today on astro-ph (accepted for publication in A&A):

http://arxiv.org/abs/0901.0974"

Particularly pertinent is the comparison of model to observation which demonstrates the bias present in observing these high redshift objects (see Fig. 3). Also of interest is the carbon abundance.

The metallicity of the most distant quasars
Authors: Y. Juarez, R. Maiolino, R. Mujica, M. Pedani, S. Marinoni, T. Nagao, A. Marconi, E. Oliva
(Submitted on 8 Jan 2009)

Abstract: We investigate the metallicity of the broad line region (BLR) of a sample of 30 quasars in the redshift range 4<z<6.4, by using near-IR and optical spectra. We focus on the ratio of the broad lines (SiIV1397+OIV]1402)/CIV1549, which is a good metallicity tracer of the BLR. We find that the metallicity of the BLR is very high even in QSOs at z~6. The inferred metallicity of the BLR gas is so high (several times solar) that metal ejection or mixing with lower metallicity gas in the host galaxy is required to match the metallicities observed in local massive galaxies. On average, the observed metallicity changes neither among quasars in the observed redshift range 4<z<6.4, nor when compared with quasars at lower redshifts. We show that the apparent lack of metallicity evolution is a likely consequence of both the black hole-galaxy co-evolution and of selection effects. The data also suggest a lack of evolution in the carbon abundance, even among z>6 quasars. The latter result is puzzling, since the minimum enrichment timescale of carbon is about 1 Gyr, i.e. longer than the age of the universe at z~6.

 

[marcus]

http://arxiv.org/abs/0901.0974"
...
The data also suggest a lack of evolution in the carbon abundance, even among z>6 quasars. The latter result is puzzling, since the minimum enrichment timescale of carbon is about 1 Gyr, i.e. longer than the age of the universe at z~6.

Matt,
that is intriguing. Suppose it's true. Suppose these things are already rich in carbon at z=6.

Why does the minimum enrichment timescale have to be 1 Gyr?
Doesn't that just mean that there were some huge early stars that got in there fast and cooked up a lot of carbon real quick?

I guess what I'm asking about is the amount of wiggle in the accepted early universe carbon enrichment story.

 

[Chronos]

I think it means back to the drawing board for nucleosynthesis. Metallization may have occurred much more rapidly in the early universe than we can currently explain - at least in the case of extremely bright objects. I don't perceive that as a threat to any cosmological model at present.

 

[matt.o]

Hi Marcus,

Matt,
that is intriguing. Suppose it's true. Suppose these things are already rich in carbon at z=6.

Why does the minimum enrichment timescale have to be 1 Gyr?
Doesn't that just mean that there were some huge early stars that got in there fast and cooked up a lot of carbon real quick?

I guess what I'm asking about is the amount of wiggle in the accepted early universe carbon enrichment story.

Well, apparently the carbon enrichment is due primarily to AGB (asymptotic giant branch) stars and planetary nebulae which evolve on long timescales. I think AGB stars are the end results of medium mass stars, thus take some time to evolve to a stage where they are expelling carbon. I'm not sure where they got the 1Gyr value from (I'd have to did deeper into the referenced papers), but I do know AGB stars and their feedback winds are hard to model in stellar population models (at least according to Bruzual and Charlot 2003) and thus there could be some wiggle room there.

 

[turbo]

Here is a recent paper. (which matt.o has referenced)

http://arxiv.org/abs/0901.0974

The current model is that mass accretes (through whatever means - there are lots of models) the quasar fires off, and then radiates strongly enough to sweep away local gas/dust so the EM radiation from the accreting BH/quasar is visible to us. This is a wonderful model at low redshifts - not so much at high redshifts, because we still have to manage to figure out how very heavy elements might have already formed and have been incorporated into the quasars, so that we can observe them at high redshift.

If we want to believe that elements heavier than those that might have been created in the BB evolve through stellar synthesis, then perhaps there is reason to explore our options. We can't reasonably expect the (accretion/stellar synthesis/nova/accretion) cycle to explain what we see.

 

[Sundance]

The form of the galaxy or cluster of galaxies is directly related to the mass and activity of the so called black hole. Black holes vary in size and activty during the evolution phases spiral to elliptical to spiral and so on with various forms in between.

Tubo the link you provided, is great reading.

The metallicity of the most distant quasars
Authors: Y. Juarez, R. Maiolino, R. Mujica, M. Pedani, S. Marinoni, T. Nagao, A. Marconi, E. Oliva
(Submitted on 8 Jan 2009)

Abstract: We investigate the metallicity of the broad line region (BLR) of a sample of 30 quasars in the redshift range 4<z<6.4, by using near-IR and optical spectra. We focus on the ratio of the broad lines (SiIV1397+OIV]1402)/CIV1549, which is a good metallicity tracer of the BLR. We find that the metallicity of the BLR is very high even in QSOs at z~6. The inferred metallicity of the BLR gas is so high (several times solar) that metal ejection or mixing with lower metallicity gas in the host galaxy is required to match the metallicities observed in local massive galaxies. On average, the observed metallicity changes neither among quasars in the observed redshift range 4<z<6.4, nor when compared with quasars at lower redshifts. We show that the apparent lack of metallicity evolution is a likely consequence of both the black hole-galaxy co-evolution and of selection effects. The data also suggest a lack of evolution in the carbon abundance, even among z>6 quasars. The latter result is puzzling, since the minimum enrichment timescale of carbon is about 1 Gyr, i.e. longer than the age of the universe at z~6.

What does this say about the age of the universe?

 

[matt.o]

Is there an echo in here?

 

[Suede]

http://www.haltonarp.com/articles/origins_of_quasars_and_galaxy_clusters":

Quasars are proto-galaxies ejected from parent galaxies.

Redshift of quasars is a function of galactic aging.

Younger quasars have high redshifts, as they mature after ejection, they become lower redshift.


hmmm... seems to fit with the data at a lot of levels no?

I'm sure we could poke holes in it, but its certainly interesting to note the problems in the data such a theory would solve.

 

[Sundance]

Quasars is the term used to explain an object that looks star like.


Quasars of various sizes and origin can be found.

The extreme case is quasars that are found in the centre of cluster of galaxies, having extreme mass, a monster jet, large surrounding halo etc.

The other extreme is where a body is ejected from a black hole such as a microquasar, a star looking body.

 

[Nereid]

Here is a recent paper. (which matt.o has referenced)

http://arxiv.org/abs/0901.0974

The current model is that mass accretes (through whatever means - there are lots of models) the quasar fires off, and then radiates strongly enough to sweep away local gas/dust so the EM radiation from the accreting BH/quasar is visible to us. This is a wonderful model at low redshifts - not so much at high redshifts, because we still have to manage to figure out how very heavy elements might have already formed and have been incorporated into the quasars, so that we can observe them at high redshift.

If we want to believe that elements heavier than those that might have been created in the BB evolve through stellar synthesis, then perhaps there is reason to explore our options. We can't reasonably expect the (accretion/stellar synthesis/nova/accretion) cycle to explain what we see.

The Juarez et al. preprint paints, in the Discussion section, a plausible explanation for why the inferred BLR metallicities of SDSS-selected quasars are roughly constant* (section 4.1, first para):

The apparent lack of evolution observed in Figs. 1–2 should not be interpreted as a lack of evolution of the BLR metallicity in individual AGNs. Indeed, Fig. 1 shows the average metallicity of the BLR in quasars that are accreting at the given redshift, but does not trace the evolutionary path of individual quasars. The apparent lack of evolution in the BLR metallicity observed in Fig. 1 likely results from a combination of the BH-galaxy coevolution and selection effects. Indeed, to cross the detection threshold of the SDSS magnitude-limited survey, high-redshift quasars must have high luminosities, hence (even if accreting at the Eddington limit) high black hole masses. Most models predict that high black holemasses must have been accompanied by the formation of a massive host galaxy (e.g. Granato et al., 2004; Di Matteo et al., 2005; Hopkins et al., 2008; Li et al., 2007), which would result into the local MBH − Mspheroid relationship. Therefore, by the time a quasar at any redshift is detectable in a magnitude-limited survey, its host galaxy must have evolved significantly and enriched its ISMsignificantly. The quasar feedback is another evolutionary effect that may yield to observational biases resulting in an apparent lack of metallicity evolution. Indeed, according to many models, during the early phases, when the host galaxy is still metal poor, the accreting black hole is embedded within the dusty ISM, and therefore difficult to detect in optical surveys. Only during the late evolutionary phases, when the galaxy is already metal rich, the quasar develops winds powerful enough to expel large quantities of gas and dust, so that the quasar becomes visible to optical observations.

The next para presents a tentative, quantitative look at this, and section 4.1 concludes:

"Summarizing, the co-evolution of black holes and galaxies, combined with observational selection effects (mostly in optical surveys), naturally explains the finding that unobscured quasars of a given luminosity appear to have on average the same metallicity at any redshift."

* do not show significant change as a function of z

 

[Nereid]

Matt,
that is intriguing. Suppose it's true. Suppose these things are already rich in carbon at z=6.

Why does the minimum enrichment timescale have to be 1 Gyr?
Doesn't that just mean that there were some huge early stars that got in there fast and cooked up a lot of carbon real quick?

I guess what I'm asking about is the amount of wiggle in the accepted early universe carbon enrichment story.

(bold added)

Juarez et al. make it clear that 'the carbon problem' needs more work before it could be said to be well-established.

The part where they discuss it - section 4.3 - is both in the Discussion section and brief (just one para long), and concludes ('this issue' is the apparent large carbon abundance in the BLR):

We note that this issue is independent of the size and mass of the BLR, making it just a pure timescale problem. Tackling this issue requires a more accurate determination of the carbon abundance, which may come from future high spectral resolution optical/near-IR observations or from future submm observations of far-IR fine structure lines (Maiolino, 2008).

In addition to the observational aspects, the relationship of the abundance of carbon in the BLR to that in the gas and stars of the host galaxy will need to be addressed, both observationally and theoretically (as matt.o has already noted). And the theoretical modelling will need to address some difficult questions about the behaviour of systems that have no counterparts in the local universe (as Chronos has already noted).

Its all fascinating stuff, and you can easily understand why it's a hot research topic.

 

[Nereid]

http://www.haltonarp.com/articles/origins_of_quasars_and_galaxy_clusters":

Quasars are proto-galaxies ejected from parent galaxies.

Redshift of quasars is a function of galactic aging.

Younger quasars have high redshifts, as they mature after ejection, they become lower redshift.


hmmm... seems to fit with the data at a lot of levels no?

I'm sure we could poke holes in it, but its certainly interesting to note the problems in the data such a theory would solve.

Arp's ideas on quasars can be left to enjoy their well-deserved, and well-earned, retirement, in the pages of the book Ideas In Astronomy That Didn't Pan Out.

In its simplest, highly summarised, form: quasars are AGNs, just as Seyfert 1s, blazars, type 2 quasars, etc, etc, etc are. They are a homogeneous class of astronomical object. Their observed redshifts are reliable indicators of their distance (in time and space), not least because dozens of (strongly) lensed quasars have been found.

Of the order of half the Strauss video, and accompanying powerpoint slides, that turbo-1 introduces in this thread, is taken up with presentation of (then) recent observational results that strengthen "The canonical modern picture of active galaxy structure" (to quote the title of slide 70). In addition, in the video Strauss talks about the Gunn-Peterson trough and how the signature of the end of the Dark Ages can be seen in the spectra of high-z quasars (just as predicted over 35 years ago, from standard cosmological models).

Oh, and as a side note, Arp's ideas on quasars must surely count as spectacular failures when subject to the Suede 'laboratory proof' test!

 

[Jonathan Scott]

From what I've been reading in the last few days, I've been getting the impression that the arguments often work as follows - I do hope this isn't really the case!

If a quasar appears to be in the middle of a galaxy, fuzzy blob or whatever, compare the redshift of the quasar and the galaxy:

1. If the quasar's redshift is higher, it must be behind the galaxy, "proving" that it is further away and hence that its redshift is cosmological.

2. If the quasar's redshift is close to that of the galaxy, it is obviously within the galaxy, "proving" that quasar redshifts are not intrinsic.

In reality, I'd hope that there would be lots of other factors taken into account, like details of spectral lines, whether the quasar appeared to be at the centre of the galaxy and so on. However, I can't help being a little suspicious.

 

[Nereid]

From what I've been reading in the last few days, I've been getting the impression that the arguments often work as follows - I do hope this isn't really the case!

If a quasar appears to be in the middle of a galaxy, fuzzy blob or whatever, compare the redshift of the quasar and the galaxy:

1. If the quasar's redshift is higher, it must be behind the galaxy, "proving" that it is further away and hence that its redshift is cosmological.

2. If the quasar's redshift is close to that of the galaxy, it is obviously within the galaxy, "proving" that quasar redshifts are not intrinsic.

In reality, I'd hope that there would be lots of other factors taken into account, like details of spectral lines, whether the quasar appeared to be at the centre of the galaxy and so on. However, I can't help being a little suspicious.

Hi JS,

I don't know how you formed this impression!

Perhaps you could explain how, in some detail?

FWIW, your description bears only a coincidental resemblance to what contemporary standard procedure is. And as an example, let's see what Juarez et al. say, in the preprint cited in several posts in this thread, about how they measured the redshifts (etc); here is section 2 (Observations) in its entirety (some formatting and characters may be lost):

We observed a sample of 30 high-redshift quasars (4.0 < z < 6.4) from the SDSS by means of near-IR and optical spectra covering at least the UV rest-frame emission lines SiIVλ1397+OIV]λ1402 and CIVλ1549, but in most cases the spectra extend to λrest ∼ 3000 − 4000Å. The original goal of most of the observations was to constrain the dust extinction in high-z QSOs. A more detailed description of the data and the results on the dust extinction will be given in Gallerani et al. (in prep.). Here we only focus on a byproduct, namely the evolution of the BLR metallicity based on the (SiIV+OIV)/CIV ratio.

Observations were obtained both with the Italian Telescopio Nazionale Galileo (TNG) in Spain and with the Very Large Telescope (VLT)-ESO in Chile. Observations were performed in several observing runs from 2003 to 2005. The observations at the TNG were obtained with the Near Infrared Camera Spectrograph (NICS) mostly with the Amici prism to obtain spectra in the range 0.9-2.3 μm at R∼75. This low-resolution mode is excellent for investigating the QSO continuum shape, but also for detecting broad emission lines. Some QSOs were observed again with the IJ grism to obtain 0.9-1.45 μm spectra at R∼500. Typical integration times ranged from ∼20 minutes to ∼3 hours. The observing strategy and data reduction are similar to those discussed in Maiolino et al. (2004).

The spectroscopic observations at ESO-VLT were done with the FORS2, along with the grismGRIS150I, to observe the range 6000-11000 Å at R∼300. These observations are mostly used to cover the short-wavelength part of some of the quasar spectra not properly sampled by the near-IR observations, but we also specifically observed a few quasars with no near-IR data with the specific aim of measuring the (SiIV+OIV)/CIV ratio. The total exposure times range from 30 to 60 minutes. For some of the z < 5 quasars observed with NICS, for which no FORS2 observations were available, we combine our near-IR spectra with optical data taken from Anderson et al. (2001).

Perhaps you are unfamiliar with the term "BLR"? It stands for "broad line region" and is not resolved in images of any quasar (that I know of), nor in the UV/optical/nearIR waveband images of any AGN either* (and, for completeness, if you can't resolve/separate something in an image, you certainly can't take a separate spectrum of it!).

Maybe a read of Maiolino et al. (2004) would help you?

* IIRC; if anyone knows of any reported observations of an AGN's resolved BLR ...

 

[Suede]

Oh, and as a side note, Arp's ideas on quasars must surely count as spectacular failures when subject to the Suede 'laboratory proof' test!

Plasmoid ejection from current pinches is a well known laboratory proven phenomina.

btw,

The Discovery of a High Redshift X-ray Emitting QSO Very Close to the Nucleus of NGC 7319
Pasquale Galianni, E.M. Burbidge, H. Arp, V. Junkkarinen, G. Burbidge, Stefano Zibetti
Astrophys.J. 620 (2005) 88-94
http://arxiv.org/abs/astro-ph/0409215

A strong X-ray source only 8" from the nucleus of the Sy2 galaxy NGC 7319 in Stephan's Quintet has been discovered by Chandra. We have identified the optical counterpart and show it is a QSO with $z_e = 2.114$. It is also a ULX with $L_x = 1.5 x 10^{40} erg sec^{-1}$. From the optical spectra of the QSO and interstellar gas in the galaxy (z = .022) we show that it is very likely that the QSO and the gas are interacting.




Probably just another freak coincidence though.

like this, NGC 7319:

or this, NGC 4319:

http://www.answersingenesis.org/images/quasar.jpg

or this, NGC 7603:

 

[Nereid]

Oh, and as a side note, Arp's ideas on quasars must surely count as spectacular failures when subject to the Suede 'laboratory proof' test!

Plasmoid ejection from current pinches is a well known laboratory proven phenomina.

In which the following have been 'proven'*:
- the creation of mass?
- atoms, nuclei, and electrons whose mass decreases with time?
- violation of conservation of momentum, energy, and angular momentum?
- violation of at least two of the laws of thermodynamics?

Not to mention that no lab has ever performed a controlled experiment on an object of mass 10^6 (or more) sols, in a volume of 1 kpc^3 (or more).

Suede, this is beyond absurd.

btw,

The Discovery of a High Redshift X-ray Emitting QSO Very Close to the Nucleus of NGC 7319
Pasquale Galianni, E.M. Burbidge, H. Arp, V. Junkkarinen, G. Burbidge, Stefano Zibetti
Astrophys.J. 620 (2005) 88-94
http://arxiv.org/abs/astro-ph/0409215

A strong X-ray source only 8" from the nucleus of the Sy2 galaxy NGC 7319 in Stephan's Quintet has been discovered by Chandra. We have identified the optical counterpart and show it is a QSO with $z_e = 2.114$. It is also a ULX with $L_x = 1.5 x 10^{40} erg sec^{-1}$. From the optical spectra of the QSO and interstellar gas in the galaxy (z = .022) we show that it is very likely that the QSO and the gas are interacting.

Yep, that's a well-known, and much discussed paper.

As with many (most?) of these Arp (et al.) papers, the 'very likely interacting' interpretation rests almost entirely on perceived alignments of features in images ... and where it doesn't, it requires a) an 'intrinsic redshift' that has no counterpart in standard physics**, and b) the 'interacting' material to have no intermediate redshift (which is inconsistent with the Arp idea you posted earlier). Further, with the widespread and easy availability of codes to model the interaction between a compact high-mass object and a galaxy, it's curious that no Arp et al. paper has been published showing the plausibility of the purported 'interaction' via simulation (with or without variable mass, etc).

Applying Occam's razor, and keeping in mind the huge amount of solid research showing that AGNs are a homogeneous class of object, we can conclude that this quasar is being viewed through NGC 7319.

* these are all core aspects of Arp's idea
** no one has published a paper showing that the Wolf effect, to take just one example, is consistent with all well-established features in the relevant spectra, for example

 

[Suede]

I'm not going to argue Arp's theory with you because doing so will result in me getting banned from these boards, which I'm sure would please you greatly.

Its enough to say I believe him and the theories that support his claim are scientifically credible, rely on known plasma physics, and don't postulate any hypothetical matters and energies.

btw,

http://www.skepticalinvestigations.org/controversies/images/NGC4319.jpg

 

[Sundance]

Arp has contributed great works in many fields.

Which part has been proven wrong?

It is not very scientific just saying that he has been proven wrong.


Neried quote

Suede, this is beyond absurd.


btw,

The Discovery of a High Redshift X-ray Emitting QSO Very Close to the Nucleus of NGC 7319
Pasquale Galianni, E.M. Burbidge, H. Arp, V. Junkkarinen, G. Burbidge, Stefano Zibetti
Astrophys.J. 620 (2005) 88-94
http://arxiv.org/abs/astro-ph/0409215

A strong X-ray source only 8" from the nucleus of the Sy2 galaxy NGC 7319 in Stephan's Quintet has been discovered by Chandra. We have identified the optical counterpart and show it is a QSO with $z_e = 2.114$. It is also a ULX with $L_x = 1.5 x 10^{40} erg sec^{-1}$. From the optical spectra of the QSO and interstellar gas in the galaxy (z = .022) we show that it is very likely that the QSO and the gas are interacting.

Which part is absurd?