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Expanding Space-time and the active vaccuum.

  1. Feb 14, 2013 #1
    There are 2 phenomena which I understand are more or less received wisdom (when seen from my pop science standpoint anyway).

    Firstly :space-time is ever expanding.
    Secondly:in a quantum "vacuum" matter/energy is continuously being created ( and disappearing) out of "nothing".

    Could there be any connection between these 2 phenomena?

    I mean ,as the Space-Time expands could it be leaving "empty space"in the wake of its expansion which was filled by these "popping into existence" quantum events?

    I am not really peddling this argument but my whole understanding of the subject would be limited to the extent that I would be happy just for someone with a better handle of what I am talking about to say words to the effect of "don't be ridiculous" ,"you have got completely the wrong end of the stick" or words to that effect (or even "by jimbo ,lad I believe you're onto something there!").

    (In my own defence I really don't have the time or the ability to study to be able to judge for myself whether my explanation has any merit or not -which is why I am hoping someone else might!)
  2. jcsd
  3. Feb 15, 2013 #2


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    Re: Expanding Space-time and the active vacuum.

    There is a connection. The acceleration of the expansion is believed to be caused by "dark energy". This is related to the virtual particle creation that you described. The theories involved are quite tentative. I presume that physicist will eventually clarify this problem. The major problem in trying to connect these two things is that there a disagreement by a factor of ~ 10120.
  4. Feb 15, 2013 #3


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    It's possible that the calculation of vacuum energy is wrong, and there is something suppressing the higher frequency electromagnetic modes, which could bring down the vacuum energy to equal the dark energy. Really, they should be the same thing: just the energy of empty space.
  5. Feb 15, 2013 #4
    Is it at all possible (aside from anything being "possible") that is is the other way round and it is the expansion of Space-Time that is creating energy in the " vacuum" ?

    Would that be a meaningless distinction? (or just meaningless....?)

    ps @mathman 10^120 is really quite a discrepancy! I understand it has been described as "the worst theoretical prediction in the history of physics"!
  6. Feb 16, 2013 #5


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    10^120 is a lot less than infinity, so it can't really be that bad.
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