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Crisis in Cosmology?

  1. Feb 18, 2005 #1

    Garth

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    There will be a conference entitled 1st Crisis In Cosmology Conference (CCC-I)

    Any takers?

    Garth
     
  2. jcsd
  3. Feb 18, 2005 #2

    saltydog

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    Do you know the history of Astronomy? It's deja vous all over again.
     
  4. Feb 18, 2005 #3

    anti_crank

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    With Eugene Savov on the organizing committee, the scientific validity of this conference is, shall we say, questionable.
     
  5. Feb 18, 2005 #4

    turbo

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    There has to be a periodic shake-up, for sure, but astronomy/cosmology is WAY overdue for a reality check.

    "Distant" quasars (z~6.5) are being discovered that are apparently being powered by black holes that have masses equivalent to several hundred billion suns. Unfortunately (for the standard model) they also have metallicities in the same range as our sun. How can this be? How can something that has existed for less than a half-billion years after the Big Bang have accreted several billions of solar masses of highly-metallized material (from first-generation supernovas, presumably) and have a metallicity equivalent to that of a star several stellar generations removed from the Big Bang? This is not an insignificant problem. (Understatement Police are dragging me away as I type!) :uhh:
     
  6. Feb 19, 2005 #5

    Chronos

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    several hundred billions

    Which observations require 'several hundred billion' solar star masses to work? What 'highly metallicized materials' are you referring to? Please provide observational examples. I think that is a bunch of bull. NOTE: we have these arguments all the time. Turbo-1 is my friend so be nice. He is a good guy. Just because I disagree does not mean he is wrong.
     
    Last edited: Feb 19, 2005
  7. Feb 19, 2005 #6

    turbo

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    These people studied 3 high-redshift quasars and found each of them had solar or super-solar metallicities AND likely exist in highly metallized elliptical or spheroidal host galaxies with masses equivalent to hundreds of billions or even trillions of suns. The quasars' SMBH cores themselves are each calculated to contain several billions of solar masses.

    http://cosmos.as.arizona.edu/~thompson/pubdb/docs/freudling03a.pdf

    Again, another paper on high-redshift quasars. There is no observed evolution in iron abundance in quasars from z=0 to z>6. Therefore, if quasars are at the distance and lookback time implied by their redshifts, they formed in regions containing materials of solar or super-solar metallicities when the universe was less than a billion years old.

    http://cosmos.as.arizona.edu/~thompson/pubdb/docs/barth03a.pdf

    It might be a "bunch of bull", but there are a LOT more papers like this in the literature, and if you follow the citations, you will see how the standard model is being constrained (strained would be a better word) by the high metallicities. Already, the model requires generations of extremely massive stars going supernova before these quasars and their massive hosts can form. The Webb telescope and the LBT will allow observations of fainter, more highly-redshifted quasars, and each one will push the BB model farther into the corner, unless we can detect an evolution in metallicity (lower metallicity in higher-redshift quasars) at some era. So far, it's not happening.
     
    Last edited: Feb 19, 2005
  8. Feb 19, 2005 #7

    Chronos

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    Well, it turns out the back half of the bull was on my side of the fence. How embarrasing. :blushing: Round conceded. The metallicity and SMBH issues are in play. Thanks for reminding me a little research can be constructive. :smile:

    Formation of the Black Holes in the Highest Redshift Quasars
    http://arxiv.org/abs/astro-ph/0406217
    ... black hole masses may reach ~10^9 msun as early as z=9 starting from stellar seeds

    High redshift quasars and the supermassive black hole mass budget: constraints on quasar formation models
    http://arxiv.org/abs/astro-ph/0311008
     
  9. Feb 20, 2005 #8

    saltydog

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    Jesus. My goodness people. Now, I love Astronomy but are we not much further than Ptolemy and his epicycles? I'm disappointed and you know, we're in a golden age of Astronomy too. Suppose they were too back then. I'm very "tolerant" though for our limitations and feel it a joy to be living during such a golden age!
     
  10. Feb 20, 2005 #9

    turbo

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    If current trends continue (discovery of even more highly redshifted quasars with solar and super-solar metallicities), what does that tell us about the Universe?

    Possibilities include:

    1) There was a Big Bang, but it occurred much longer ago than 13.7Gy. We are extrapolating redshift (as cosmological expansion) incorrectly, and the Universe is much older than 13.7Gy.
    2) There was a Big Bang 13.7Gy ago, but somehow we have "misunderestimated" (to quote President Malaprop) the rate at which heavy elements form. This may allow z~6 quasar SMBHs to form at solar-like metallicity in the <1Gy time since the BB, although this is VERY tightly constrained by time, accretion rates, mass budget, etc, and is looking less and less likely all the time. A single massive z>7 quasar with typical metallicity will probably close the door on this possibility (or as Chronos says "a stake in the heart!")
    3) There was a Big Bang 13.7Gy ago. Quasars (and perhaps some related objects) have intrinsic redshifts, so they only appear to be very distant and old. They are in fact younger and closer and are smaller with more modest luminosities. If their redshifts are not due entirely to cosmological expansion, then they do not have to be 1-10 Billion mSol SMBHs residing in Trillion mSol host galaxies. This would give the heirarchical model of galaxy formation a bit of breathing room - the current understanding of quasars requires that the most massive and active galaxies formed very early, which stands the H-model on its head. Of course Arp, the Burbidges, and others have been roundly ridiculed for proposing the concept of intrinsic redshifts, so the astronomical community is going to avoid this possibility like the plague.
    4) There never was a Big Bang. We live in a steady-state universe in which even the most distant things we can ever see are roughly equivalent in metallicity to stars in own neighborhood. "Cosmological" redshift is not due to expansion of the universe, but to energy loss as EM interacts with the fields through which it propagates. The more distance EM has to travel, the more it is redshifted. Another "third rail" idea that can kill the career of an astronomer, but what if it's true?

    There are lots more possibilites, including VSL, and perhaps some mix-and-match combinations of the above, but you can see where this is going. Standard-model cosmology has a lot of problems, requiring the invention of non-baryonic dark matter, dark energy, inflation, etc, to keep it afloat. It is impossible to refute all these epicycles, just as it is impossible to refute any ideas that are taken on faith. The observed high metallicities of high-redshift quasars WILL cause all these ideas to be challenged, though. It is just a matter of time. When Webb comes on-line, or when the LBT is fully operational and some spunky graduate student measures super-solar metallicity in a quasar at z~7-8 or so, the 13.7Gy Big Bang universe will be absolutely untenable. Hopefully, the standard model will be seriously re-evaluated and not just patched with another epicycle or two. The next several years will be an interesting time.
     
  11. Feb 20, 2005 #10

    Garth

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    One viable possibility, yes you have already guessed it, is Self Creation Cosmology!

    SCC nucleosynthesis, (i.e. in its Einstein conformal frame) is that of the linearly expanding or “Freely Coasting” Cosmology in which the process lasts much longer than in the standard model. This results in a high primordial metallicity and an age of 14.4 Gyr. DM is baryonic (- mainly black holes?) and DE is not required at all. The freely coasting models, SCC or otherwise, do not require Inflation in the first place and so saltydog three of those epicycles are dispensed with at a stroke.
    Two problems with the theory is that the present non-observation of DM requires explanation and deuterium has to be produced by spallation.

    However the theory is being tested at this moment by the Gravity Probe B satellite experiment, and we hope for a result early next year.

    Garth
     
  12. Feb 20, 2005 #11

    Chronos

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    Deuterium abundance is a problem in just about every model, so SCC is in good company. And CDM has always been a thorn as well. While mechanisms like MOND are appealing, evidence of exceptions to that explanation are also too numerous to be disregarded. I think it is unlikely we can come up with a working model that does not include some amount of CDM in a form not yet detected.

    There are some big pieces missing in the puzzle, and we have pretty much been stumbling around in the dark searching for them. I like to think the LHC will produce some of the answers. It appears promising we may find the elusive Higgs boson. And that in itself would be a remarkable achievement. But reaching the planck energy is out of the question and it is very optimistic to hope to find a lower threshold, as suggested by some higher dimensional models.

    There some other interesting ideas afloat:

    Structure in a Loitering Universe
    http://arxiv.org/abs/astro-ph/9212002

    Did the Universe loiter at high redshifts?
    http://arxiv.org/abs/astro-ph/0410221
     
  13. Feb 20, 2005 #12

    Q_Goest

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    How about string theory and Branes? Do these hold any hope at resolving discrepancies?

    How about other theories such as loop quantum gravity?
     
  14. Feb 21, 2005 #13

    Garth

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    Here is another paper, published today, " A case for nucleosynthesis in slowly evolving models " on the concordance of the freely coasting model with cosmological relative abundances and other constraints.

    Garth
     
    Last edited: Feb 21, 2005
  15. Feb 23, 2005 #14

    Garth

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    Another problem with the standard model is the non random alignment of the large scale multipoles as in Kate Land and Jo˜ao Magueijo's paper published today The axis of evil
    Does this constitute a "crisis"?

    Garth
     
    Last edited: Feb 23, 2005
  16. Feb 23, 2005 #15

    turbo

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    Garth, the paper you linked to is not the one you quoted from, but it is compelling reading nonetheless, touching on problems the BB exhibits in regard to neucleosynthesis, elemental abundances, etc.
     
  17. Feb 24, 2005 #16

    Garth

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    Whoops sorry this is what I meant: The axis of evil
    :blushing:

    Again, "Does this constitute a 'crisis'?" If not then how about, and on a different tack, this paper, which was revised on the physics-arXiv today Evidence for new physics from clusters ?
    Baryonic DM?

    Garth
     
    Last edited: Feb 24, 2005
  18. Feb 24, 2005 #17

    Phobos

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    An excellent perspective, saltydog.
     
  19. Feb 25, 2005 #18

    Chronos

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    While many problems remain, the 'standard' model is still very sound. I don't understand why it is so robustly attacked. I have yet to hear a lucid argument to the contrary that makes any sense.
     
  20. Feb 25, 2005 #19

    Garth

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    First it is good science to question even the best established theories. Secondly I question your definition of "very sound": no Higgs Boson, no identified non-baryonic DM particle/s, no identifiable DE, very early evolved structures, early metallicity, lack of low l WMAP fluctuations, where do I stop? Now there may be solutions to these anomalies within the standard model but until then I would not count that model to be robustly established.
    Furthermore, the fact that the consensus opinion among the cosmological community does think it is sound is even more cause for concern.

    Garth
     
    Last edited: Feb 25, 2005
  21. Feb 25, 2005 #20

    turbo

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    You are absolutely right. Here is a quote from the good doctor. While he would certainly find satisfaction in the concept that his work is still regarded as valuable, I think he would shudder at the thought that any real physicists would consider his theories perfect and complete. It was not in his nature to treat any scientific ideas as if they were somehow sacred or unquestionable.

    "How does it happen that a properly endowed natural scientist comes to concern himself with epistemology? Is there no more valuable work in his specialty? I hear many of my colleagues saying, and I sense it from many more, that they feel this way. I cannot share this sentiment. ...Concepts that have proven useful in ordering things easily achieve such an authority over us that we forget their earthly origins and accept them as unalterable givens. Thus they come to be stamped as 'necessities of thought,' 'a priori givens,' etc. The path of scientific advance is often made impassable for a long time through such errors. For that reason, it is by no means an idle game if we become practiced in analyzing the long common place concepts and exhibiting those circumstances upon which their justification and usefulness depend, how they have grown up, individually, out of the givens of experience. By this means, their all-too-great authority will be broken."

    Einstein
     
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