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Cosmic Slow down

  1. Jun 5, 2013 #1
    A paper appeared on the arxiv today claiming that the acceleration of the universe is slowing down:


    they reference a few other papers also claiming to see the same thing.

    How robust do we think these reuslts are? If so what does it mean for dark energy being something variable rather than a cosmological constant?
  2. jcsd
  3. Jun 5, 2013 #2


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    I'm taking a wait-and-see attitude on that one. Just as a BTW side observation you might want to look up the authors e.g.
    He's the one whose name I recognize (21 papers, avg. no. cites = 4.0 excl. self-cite)
    The other two have no prior papers listed on Inspire.

    The paper they CITE is by Starobinsky et al. Starobinsky is well-known and that paper has over 100 cites.

    I thought it might be worth looking at the list of cites of the Staro. paper to see which recent papers have RESPONDED to it. I took a quick look and didn't see anything interesting. There was a 2011 paper by Starobinsky himself et al, but it was somewhat more reserved and tentative, or so I thought.

    My impression FWIW is that nothing much has come of this so far.
    Last edited: Jun 5, 2013
  4. Jun 5, 2013 #3
    Thanks Marcus, I guess that new paper is only out today so we shall see if anyone takes it seriously.
    If it were to be confirmed what would it imply for the cosmological constant - not so constant after all? or could we explain the slow down via other effects?
  5. Jun 5, 2013 #4
    Looking over the paper it seems to indicate a variable constant however they used a limitted data set, some of the reference sets were fairly old. So based exclusively on this article I wouldn't think it will go far but that is just my take on it.
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