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Vacuum energy in gravitational fields

  1. Aug 1, 2004 #1


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    Some time back, I asked if there was anyone doing work studying the effects of gravitational fields on virtual particle pairs. Tonight I found this paper (see section 4) - is there someone here who can steer me to similar work?

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  3. Aug 2, 2004 #2


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    Exciting paper!

    Paper by Robert Caldwell (Dartmouth). Using the Casimir-effect as a model, he calculates that gravitational fields can cause variations in zero-point energy. If zero-point energy is truly the source of the cosmological constant, then it cannot actually be constant.

  4. Aug 2, 2004 #3


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    I tried to find more about this by looking in Citebase for
    articles that cite Caldwell
    but I found only two, and this was IMO the more on-topic one:

    "Casimir effect and vacuum energy"
    Cyriaque Genet, Astrid Lambrecht, Serge Reynaud
    10 pages, IAP Colloquium "On the nature of dark energy"

    this cites caldwell right at the end, in the conclusions.

    I agree that zero point energy cannot be constant and I would like to
    understand better how Caldwell says it is effected by the gravitational field.
    Let's hope more articles about this show up. I was disappointed not to find more in Citebase. Glad you found this, turbo.
  5. Aug 2, 2004 #4
    I was Looking for a Way For Space Travel


    I underlined that statement specifically for you Marcus.

    Last edited: Aug 2, 2004
  6. Aug 2, 2004 #5
    Robert Caldwell is the creator of the model known as "Phantom energy", and he shall do whatever thing to dismiss the possibility that dark energy has constant density
  7. Aug 2, 2004 #6


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    Is there a good reason why dark energy should have a constant density, other than simplifying calculations for physicists? :rolleyes:

    If dark energy is really zero-point energy and zero-point energy (as demonstrated the the Casimir effect) can be eliminated from an area by simply restricting the physical space in which virtual pairs can form, then one would expect that massive objects like planets, stars, etc, would be huge voids in the dark energy field. I find it easier to understand variations in dark energy density than to believe that its density must be constant under all curcumstances. If we accept a causal agent for dark energy that can be excluded by matter or by bounding very small areas with matter, then we must be prepared to accept that it is not an all-pervasive field of constant density.
    Last edited: Aug 2, 2004
  8. Aug 2, 2004 #7


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    I was very happy to find this, too and would like to know if there are any other studies in this vein. There is a reason for my madness: If gravitational fields can produce preferred orientations in the alignments of virtual particle pairs, it *may* be possible to exploit that pervasive sea of energy. Perhaps not here on Earth, but how about for space propulsion? I know this is NOT the forum to posit this, but if gravity can orient virtual pairs, and we could produce a boundary that preferentially passes particles in one direction and anti-particles in the opposite direction, or passes either particles or antiparticles while rejecting their opposites, we may be able to create a pressure gradient in zero-point energy across this boundary to use as thrust. :rolleyes: I would love for humans to explore space, but at the expense of the already-existing energy of the vacuum, not by trying to throw reaction mass away.

    If virtual pairs cannot be oriented by gravitation, solar wind, etc, then our attempts to break their bonds will probably cost way more energy than we can recover. Preferential orientation of the pairs would make exploitation of ZPE conceivable, if not practical.

    I just noticed the title on your post, Sol. If we can create a boundary that exploits possible gradients in the ZPE field (be they preferential pair orientation, field density, etc) we've got a chance of going to the stars.
    Last edited: Aug 2, 2004
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