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Dark Energy

  1. Nov 18, 2006 #1
    Latest data from Hubble indicates that:
    What are the ramifications of this finding for the various TOEs we have?
  2. jcsd
  3. Nov 18, 2006 #2
    I think it might confirm the existence of a Zero Point Energy which has been controversial in the past. This energy is the minumum possible energy state of the quantum fields that are associated with every point in space no matter where. And it would confirm those theories that predict a QFT of spacetime/matter that give rise to added space with time as part of that QFT.
    Last edited: Nov 18, 2006
  4. Nov 19, 2006 #3
    I saw this in the press lately too. Seems to me space always has to preceed matter, so there is always space "outside" a universe. If there were a cloud of particals in a universe, they would naturally have to expand just because of brownian motion. Say the motion of any one partical in the cloud is essentially random. There necessarily have to be lots more directions away from the center than there are directions towards the center. I should like to know if there is anything in the cosmological constant, or in dark energy, which makes it exceed the limits of this simple model. But before you throw in the inevitable thinning of the density of matter, please take into account that the "Particals" here may be the size of strings, making our usual bosons and leptons almost unimaginably huge by comparison. And on that scale, self-creation may be operating, as virtual particals become real as more space becomes available to accomodate them.


  5. Nov 21, 2006 #4


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    I was reading the Riess paper on Arxiv over the weekend:

    New Hubble Space Telescope Discoveries of Type Ia Supernovae at z > 1: Narrowing Constraints on the Early Behavior of Dark Energy

    I think it is more a confirmation of earlier work by Perlmutter et al that put accelerated expansion and dark energy on the cosmological map. This will probably draw more interest on the A-C forum. I was about to start a thread there on this paper, but noticed alexsok got the jump on me here. I will credit accordingly.
  6. Nov 21, 2006 #5


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    Havn't had time to read myself yet, but I've heard it was quite hard to extract what they really conclude. Appearantly there's a lot of assumed priors in many of the calculations which makes the situation somewhat unclear. What did you get out of it?
  7. Nov 22, 2006 #6
    The new result might be an indication that dark energy is fundamental rather than environmental. Conversely, had dark energy been significantly different 9 billion years ago, it would have been strong evidence that it were environmental.
  8. Nov 22, 2006 #7


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    Yes, that much I'd got. But for example, what limits are they putting on dw/dz?
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