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Quasars are closer, less massive, not as bright.

  1. Dec 23, 2004 #1

    wolram

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  3. Dec 23, 2004 #2
    Uh? I've never heard of this thing called CREIL redshifting, but the authors say that is the main component of the spectra of quasars, and consequently these objects are not so far away. Hence, here is another theory that can be put in the same category as Arp's intrinsic reshift theory. Curiously, the authors say that both quasars and Seyfert galaxies are indeed neutron stars (!?!?!)
     
  4. Dec 24, 2004 #3

    Chronos

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    There is probably a reason this paper has not been published. The authors are among a small, dedicated group of Arp adherents. It is not surprising the term CREIL is unfamiliar. It was coined by one of the authors in this paper:
    http://arxiv.org/abs/Astro-ph/0305180]
    The concept is similar to that of 'plasma redshift' championed by a dude named Ari Brynjolfsson's. His work is also rather off-road and distant from the nearest scientific interstate.

    For some illuminating insights offered by Jerry Jensen [one of the authors] try:
    http://www.badastronomy.com/phpBB/viewtopic.php?t=14433
    I was particularly taken by his name-dropping reference to 'Halden Arp'

    For some illuminting insights offered by the co-author, Jacques Moret-Bailly [he goes by the initials JMB in the link that follows], try:
    http://www.universetoday.com/forum/index.php?showtopic=2916
     
  5. Dec 24, 2004 #4
    Good one. Indeed he says "Halpen Arp", but is ridiculous anyway. The fact that he don't know the true name of Arp talks very badly about his knowledge of astronomy, and in particular about the CREIL effect that he postulates having importance in redshifts
     
    Last edited: Dec 24, 2004
  6. Dec 24, 2004 #5

    ohwilleke

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    There is no sin in agreeing that Arp has identified problems in the current approach. This is as far as the praise of Arp goes. Indeed, the authors deliberately distinguish themselves from questionable Arp conclusions (such as jets) in the paper.

    The article is not the best written, but the agenda of the article -- describing a laboratory scale experiment that produces results that can be confused for red-shift, and using those conclusions to match quasar data and using that data to show why CREIL is a better explanation of the data than true redshift, is eminently respectable and reasonable, although, e.g. short on illustrations that would compare red shift v. CREIL predictions v. data.

    Put it this way. If CREIL operates as advertised, then the conclusions follow. They are hardly great leaps of logic. And CREIL has the virtue of being a testable phenomena. So simply dismissing the authors based on reputation or association proves too much. Anyone who disagrees with existing cosmology is necessarily going to have some sympathy with others with question the existing cosmology to some degree because all are going to be concerned about data, like quasars and non-baryonic matter, which seem most extraordinary. To dismiss studies simply because of such shared views, is simply to say that standard model cosmology is right because it is right.
     
  7. Dec 24, 2004 #6

    Chronos

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    CREIL is a hypothetical offshoot of the Raman effect that has not been experimentally tested. Per Jerry Jensen:

    "...CREIL has always been based on the tensors of polarization, not Raman scattering- in the last paper, the one Jacques and I coauthored, we specifically state the name is a little missleading, but has been retained for history reasons."

    While I did not entirely follow the explanation given, the tensors of polarization apparently imbue space with a refractive index. It also offers an explanation for MOND and the Tully-Fisher relation. I did not follow that very well either.

    Your points are valid. Nothing should be dismissed out of hand. My intent was to point out it is a speculative theory that does not have as much observational support as more widely accepted models. Such theories should be viewed more critically than those that are on a firmer footing. And reputation is a consideration. Researchers with a solid history of high quality work are entitled to a little more wiggle room than those with a history of taking controversial positions. Those who think outside of the box will always be held to a higher standard of proof.
     
    Last edited: Dec 24, 2004
  8. Dec 26, 2004 #7

    turbo

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    Here is a fellow that says space is filled Rydberg Matter and that Stokes Raman scattering through polarized Rydberg Matter is responsible for cosmological redshift. He cites quantized redshifts in the local supercluster as evidence of this process. There seems to be quite a bit of interest in non-cosmological redshifts these days.

    http://www.kluweronline.com/issn/0004-640X
     
  9. Dec 26, 2004 #8

    Nereid

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    There has been considerable interest in non-cosmological redshifts, from day1 (Hubble's first, landmark paper); and there will likely continue to be for at least another century or more.

    I'd just like to add a few words to ohwilleke's and Chronos' posts ... IMHO, there are two different strands (to turn up the contrast) - exploration of physical effects which can give rise to redshifts (of the kind observed by astronomers, across the spectrum from gamma to radio), and (radical) re-interpretation of millions of astronomical observations.

    Wrt the former, it's always exciting to find some new physics at work, especially if it can be clearly tested and signals distinct from well-known phenonema observed (or not). From reading the links which Chronos posted, I don't have a good feeling for the observational results which validate CREIL ... if the effect is as described, it should show up clearly in a range of astronomical observations, and much of the data for these is (AFAIK) in the public domain.

    Wrt the latter, I think someone posted an Ari Brynjolfsson paper here some time ago. He certainly has an ambitious programme; apart from 're-explaining', it would be interesting to see what 'new' phenomena he predicts, or tests which could clearly distinguish his idea for standard cosmology (or indeed a great deal of standard galaxy, cluster, and even Local Group astrophysics).

    For those who wish to re-interpret (some?) quasar redshifts as being non-cosmological, here are some of the challenges:
    - resolved underlying galaxies (for some quasars)
    - 'background' quasars (e.g. lensed by foreground galaxies or clusters)
    - ALL details of the Lyman forest spectra
    - 'dark' quasars (i.e. visible in X-ray and IR/radio; invisible in the optical)
    - quasars seen 'through' the galactic plane vs those at high galactic latitudes (if the observed redshift is 'local', and proportional to H column density, there will be a clear galactic latitude signal in the redshifts)
    - models of quasars consisent with ALL observed quasar phenomena (i.e. if quasars aren't distant SMBH accretion disks, jets; AGN, etc, what are they?)
     
    Last edited: Dec 26, 2004
  10. Dec 27, 2004 #9

    ohwilleke

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    The filp side, of course, and the reason that so much attention is focused on quasars is that quasars are outliers.

    They are distributed overwhelmingly at very high redshift (z>2 on average and in some instances z>5). If that redshift entirely implies distance, then quasars must be extremely massive (on the order of 100s galaxies) and yet must have excedingly narrow radii to account for the rapid variations in luminosity (assumed to be due to rotation). Seeming interactions of quasars and more local objects must all be optical illusions. In contrast, if some of the redshift is due to something other than distance, than quasars could be much smaller in size (perhaps on the order of magnitude of a typical star), would have radii typical to stars, and would have luminosity on the order of magnitude of stars and can be in systems with stars and galaxies. Suddenly, tens of thousands of extreme outliers become one more class of star like objects that just happens to exhibit spectra which can be confused for highly redshifted spectra.

    Yet, if the early universe is dominated by huge objects with masses of 100 galaxies+ why does the modern universe lack such huge objects? What would be pushing these clumps of matter apart?

    Also, while in the case of Cepheid standard candles we can observe such stars close up and use them to calibrate our redshift yardstick, we don't have the same luxury with quasars. We don't have any close quasars to use as a reference that could be used to compare distant quasars, and in the standard theory we also lack any non-quasar objects closely associated with quasars that we can used to say, e.g. a quasar at this known distance (through means other than redshift) looks like x. We can certainly say that one quasar is shifted relative to another quasar, but the original spectrum is theory dependent.

    Also, quasar theory lacks the seasoning of many other parts of modern cosmology. General Relativity and Quantum Mechanics are ideas that have been kicking around since before 1920. The first quasar was observed in 1963, and large data sets (now in the mid to high thousands), have been around for a much shorter time period.

    Because the phenomena posited to be behind quasars is more extraordinary than that behind other phenomena in astronomy, it requires more extraordinary proof and alternatives are more paletable. Also, while quasars are meaningful details in theories of early cosmology, some form of intrinsic redshift in quasars by some previously unconsidered by plausible means would not shake up any other realm of physics unduly.
     
    Last edited: Dec 27, 2004
  11. Dec 27, 2004 #10

    turbo

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    There are some huge benefits that accrue if quasars are found to have intrinsic redshifts, not the least of which are:
    1. The paucity of "local" quasars is explained as a misinterpretation of redshift as cosmological distance. Then maybe the universe can be isotropic and homogeneous, as it is presumed to be.
    2. Quasars no longer need to be emitting energy equivalent to perhaps 100 galaxies in a volume smaller than our solar system. The Chandra site has a non-technical treatment of this quandry:
    http://chandra-ed.harvard.edu/3c273/tiger.html
    3. The hierarchical model of galaxy formation may retain some semblance of usefulness. Presently, quasars turn that model upside down, representing very dense concentrations of matter and energy very early in the 13.7Gy-old BB universe. How did such huge, extremely energetic objects have time to form so soon after the Big Bang?

    Go to the (still pretty new) Google Scholar link, type in the name "Burbidge" and/or "Hoyle" and read a few papers relating to cosmology. Arp is the whipping boy for lots of these folks because of his stature as an observational astronomer, but he is not a lone iconoclast. Check some of these papers on CiteBase, and see where they lead you.
    http://scholar.google.com/
     
  12. Dec 27, 2004 #11

    Nereid

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    Indeed, but there are other reasons too.
    Why?
    To be pedantic, 'small' would be a better term than 'have excedingly narrow radii'
    If you count gravitational lensing as 'optical illusions', then yes; if you're thinking of Arp's lists, then I'm not aware of any for which the apparent association with a 'local' object remains strong.
    Indeed; like AGN, or BL Lac objects, or Seyferts, or ...
    Well, no; all manner of good observations would then need a different model ... such as the quasars which appear to be just where galactic nuclei would be ... of the galaxies they seem to be in (IIRC, very soon after the first quasars were observed, some astonomers - Sandage? - noted that several appeared to have 'fuzz' around them, and others appeared to be not quite point sources; the latest in this line is, of course, the HST observations ... pity that the coronograph won't fly :cry:), the lensed quasars, ALL aspects of the Lyman forest (not just the existence of sets of absorption lines), the lack of anything even remotely like quasars 'locally', the well-observed 'pure luminosity evolution' of quasars, quasars whose underlying galaxy has the same redshift as the quasar, Lyman forest lines that correspond to the redshift of galaxy (clusters) through which they seem to pass, ...
    So what are AGNs? What's the correspondence between SMBH in galaxy nuclei (well observed) and quasars? (can you provide a link to models which demand that quasars have masses >10^11 sol?)
    It's fairly easy to list observations that could fill this gap ... I expect JWST, SNAP, perhaps even some of the AO and optical interferometric instruments+scopes being planned at '8m class' observatories (e.g. Keck, VLT) will shed some light on this.
    Er, no; it's the same as that for AGNs, Seyferts, BL Lac objects, ...
    Taste is a rather personal thing ... and 'proof' surely not to be found anywhere in any science ... but for some, the mountain of good observations consistent with quasars' redshifts being cosmological goes down well.
    I guess that depends on what the 'previously unconsidered by plausible means' is (or are)! :smile:
     
  13. Dec 28, 2004 #12

    Chronos

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    Supernova 1a are the candles, no need for Cepheids. Perhaps the quasar population at high redshift is related to their intrinsic brightness. Perhaps only enormously bright entities are visible at such distances. There is no apparent need to reinvent physics to explain that. There is an apparent need to reinvent physics to fit intrinsic redshift. CREIL creates more questions than it solves.
     
  14. Dec 28, 2004 #13

    Nereid

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    No need for exotic explanations ... the 2dF data on quasar luminosity vs redshift accounts of this paucity quite nicely ... quasars exhibit 'pure luminosity evolution'
     
  15. May 27, 2005 #14
    curved space

    Re the above quote from wolram:

    They can be less massive and not as bright without being closer. Here's why: We use the inverse-square law to infer their absolute brightness from their apparent brightness and their distance. The inverse-square law is true for a "flat universe," but not for "positively curved space" (e.g., the hypersurface of a four-dimensional hypersphere). To see why, picture the surface of a three-dimensional sphere (since it's hard to visualize three-dimensional space curved into a fourth dimension). This surface is a two-dimensional space curved into the third dimension. Imagine two-dimensional creatures, stars, and light rays restricted to this surface. These creatures will think that their "universe" goes on forever in two dimensions.

    Let's define the "North Pole" of this two-dimensional universe to be at a star. Light from this star spreads out from the North Pole toward the "equator" and then converges toward the "South Pole." Now imagine a two-dimensional observer south of the equator and moving southward. Because the light from the North Pole is converging toward the South Pole, this observer will see the star getting brighter as he moves farther away from it (i.e., from the equator toward the South Pole).

    For the same reason, we in our three-dimensional universe will see
    an object getting brighter as we get farther away from it, if our
    universe is positively curved and if the object is sufficiently far away. This, of course, contradicts the inverse-square law that we tend to take for granted. Hence, assuming the inverse-square law will lead us to the erroneous conclusion that far-away objects are brighter than similar close objects. This may be a reason why we infer such a large absolute brightness of quasars.

    Of course, my conclusion is based on the assumption of a positively curved universe, which is not proved beyond all reasonable doubt. So it's not gospel truth, but it's something to think about.
     
    Last edited: May 27, 2005
  16. May 27, 2005 #15

    ohwilleke

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    The evidence thus far is that the universe is very nearly flat, indeed far more flat than many people had suspected. The evidence that the universe is not positively curved to any meaningful large scale degree is at least "clear and convincing" (hey, you started the legal terminology, and, as a lawyer, I had to take the bait). The possibility that the universe might be curved may not be "frivilous", but there is virtually no evidence a positive space curvature on the scale you suggest.

    The possibility that quasar data might be misinterpreted is certain there. But, I don't think that significant positive space curvature is a likely prospect to show that effect.
     
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