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Cosmology getting stale with discoveries?

  1. Mar 19, 2008 #1

    I was an avid amateur cosmologist for a few years, but lost interest 2 years ago. What I recall is a few basics like:

    1) Univ is ~13.7 billion years old
    2) Univ is accelerating in expansion
    3) WMAP measured ~2.75 Kelvin vaccum temp.
    4) Space is indeed flat Euclidean geom.
    5) Only 4% of Univ mass is ordinary matter
    6) Hubble constant ~71km/pc

    From memory, those were the most basic aspects of cosmology. My question is if any of these have changed over 2 years and is there any new data that fundamentally changes any of these?

    All I've read recently (very little) is that the newest WMAP survey is refining our numbers slightly, but no major revelations have come forth. Fine structure constant is still about what we thought it was, right?

    So where oh where are the new discoveries and theorums in cosmology? It was so vibrant 5 years ago and now it seems, to this amateur, to be stagnating in minutia. Refining here, tighter boundaries and limits there, but no new big discoveries...

    Am I wrong? Pick me apart.
  2. jcsd
  3. Mar 20, 2008 #2
    I too think the same..most of the discoveries related to cosmology like hubble's redshift, CMBR were done half a century back and we are only refining those ...no new big discoveries...
  4. Mar 20, 2008 #3


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    So dark matter and dark energy does not count as big discoveries?
  5. Mar 20, 2008 #4

    George Jones

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    At least until (and maybe well beyond) we sort out dark energy and dark matter, there is big game afoot in cosmology.
  6. Mar 20, 2008 #5


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    You're basically correct that the last five years has mainly put harder limits without detecting anything "new". (Although I find that important as well.)
    But I would say the realistic expectations for finding something "new" up to now has not been very high either. E.g. when it comes to dark matter searches, recent experiments have just touched upon the interesting parameter space of dark matter candidates.
    Now that LHC, and a number of exciting astrophysical experiments, are on the way, the expectations are much higher. So please hold on for a few more years.
    If those will not find anything "new", I think you have the right to be dissapointed, but not right now...
  7. Mar 23, 2008 #6
    Oh yes, I agree LISA and the LHC will likely make some exciting discoveries in the next 5-10 years. For now, there is a bit of a lull, I mean how many covers can Scientific America do of dark energy before there is new news.
  8. Mar 23, 2008 #7
    Yes the fallout in both cosmology and physics is unpredictable at this time.
  9. Mar 23, 2008 #8


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    Heh heh, SciAm covers are maybe not the best index of vitality and activity in a field, Little Brother.

    What gets publicity in Pop Sci media is often just chaff.

    Quantum cosmology is at the leading edge and to properly assess you have to look at CITATIONS and PEER REVIEW publication in contrast to science journalism.

    I can TELL you that revolutionary change is afoot in cosmology, or you can look for your self. Try looking. Go here
    and do a search for keyword quantum cosmology and date > 2005 (just to get RECENT work)

    this is the result

    here I have the papers ranked by cite count (apparent importance to other researchers) and I used a "desy" keyword search where you say "DK quantum cosmology" instead of meerly "K quantum cosmology". You can see how to vary the search parameters just by going with the link.
    Last edited: Mar 23, 2008
  10. Mar 23, 2008 #9


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    when you go to spires and rank recent papers by citation count you see what the
    dominant mainstream work in quantum cosmology is.

    What you need to know is that essentially ALL of that work finds that the big bang was a bounce. And it runs its models back into a collapsing phase before the start of expansion.

    But these people are not string theorists----they do very little self-publicity in the media.
    this is a revolutionary change in cosmology and you can see who the main authors are.
    Ashtekar, Bojowald, Param Singh, Tavakol... For the most part they just quietly do their work and don't spread a lot of hype around in the media. You find out where the work stands in the scientific community when they get invited to present it at major conferences. For example Ashtekar is giving an invited talk at the APS meeting in April. He was elected president of the professional organization that puts on the GR conference every three years. Bojowald was awarded the organizations top prize for his research. That is the kind of thing one looks for, in my view, not Scientific American covers.

    Besides getting past the big bang singularity, quantum cosmologists are exploring possible mechanisms to explain inflation and possible dark energy alternatives. There are too many ideas of this sort being discussed for me to pick out any front runners.
    At least one will be featured in a chapter of the new book coming out this July called Beyond the Big Bang. This is available for pre-order from Amazon

    It is a 600 page book with about 20 authors all of whose research is concerned with modeling pre-big bang, and discovering ways to test and rate the various models. I see no reason to expect that the book's appearance will be accompanied by a media splash, since the general public is not the intended audience.
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