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Possible solution for dark energy

  1. Feb 2, 2005 #1

    wolram

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    http://xxx.lanl.gov/pdf/astro-ph/0309679
    Mechanism for vanishing zero point energy
    Robert D klauber. Jan 2005.
    This paper is way beyond my ken, if anyone has an interest, will
    they please explain the basics.
     
  2. jcsd
  3. Feb 2, 2005 #2

    wolram

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    The paper also suggests a solution to dark energy.
     
  4. Feb 2, 2005 #3

    jcsd

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    The problem with zero point enrgy in cosmological theories is that it leads to a ridculously large cosmological constant*, what this paper claims to do is to resove this problem by offering a mechaism so that the effect is cancels giving a zero cosmological constant. It also claim that slight assymetries could lead to non-zero, but sensibly sized cosmological constant that could explain the obsrevations of so-called dark energy.



    * http://super.colorado.edu/~michaele/Lambda/phys.html
     
  5. Feb 2, 2005 #4

    wolram

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    By JCSD
    The problem with zero point enrgy in cosmological theories is that it leads to a ridculously large cosmological constant*, what this paper claims to do is to resove this problem by offering a mechaism so that the effect is cancels giving a zero cosmological constant. It also claim that slight assymetries could lead to non-zero, but sensibly sized cosmological constant that could explain the obsrevations of so-called dark energy.
    -----------------------------------------------------------------
    Yes i understood upto this point, but what is the cancelling mechanism?
     
  6. Feb 2, 2005 #5

    jcsd

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    Hmm you'd to ask one of the 'QFT guys' for detailed answer, but what it appears to tlak about is the inclusion of solutions in QFT previosuly disgarded for representing negtive enegry states that cancel out the effects of zero point energy in cosmologicla models.
     
  7. Feb 2, 2005 #6

    wolram

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    Do you think it best to move this thread, if so will a moderator please
    do so.
     
  8. Feb 3, 2005 #7

    wolram

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    He talks about negative frequencies and supplemental solutions.
    I guess this means that that the negative portion of the field is
    ignored in calculating the total energy, and if it is included the
    total energy is near to zero, this is obviously a very simplistic
    explanation, and i cannot see why it has been ignored by others
    if it that obvious.
     
  9. Feb 3, 2005 #8

    hellfire

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    I do not understand why does the author claim that these are "supplemental" solutions. I think that when one expands the field (e.g. the Klein-Gordon field) in fourier modes, these modes form a complete basis of solutions to the field equation. Changing w to -w may result in a change of basis, but not in a new solution. Am I wrong? Actually, this is not a relativity but a QFT question.
     
  10. Feb 3, 2005 #9

    jcsd

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    I think he may very well be re-interpreting the solutions, unfortunately I don't really know enough to comment.
     
  11. Feb 3, 2005 #10

    wolram

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    Thankyou for your help JCSD , but i am far from an understanding
    of this paper, if anyone has some inkling as to what it is about i will
    be happy to here from them
     
  12. Feb 3, 2005 #11

    Garth

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    Interesting approach...
    It is a scalar -tensor theory in which the scalar field is coupled to mass by the wave equation. Reversing time gives you a second set of solutions which are normally discarded, they go backwards in time, and the author finds that if these are included in a quantum field theory you end up with a gravitational theory that resolves the 'lambda' (ZPE) and the Dark Energy problems.

    Garth
     
  13. Feb 4, 2005 #12

    wolram

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    By GARTH
    Interesting approach...
    It is a scalar -tensor theory in which the scalar field is coupled to mass by the wave equation. Reversing time gives you a second set of solutions which are normally discarded, they go backwards in time, and the author finds that if these are included in a quantum field theory you end up with a gravitational theory that resolves the 'lambda' (ZPE) and the Dark Energy problems.
    -------------------------------------------------------------------------------
    Thank GARTH
    By reversing time, is it meant that he is looking at the history of the field,
    or is he reversing in a pure mathematical way?
     
  14. Feb 4, 2005 #13

    Garth

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    Most physical equations are time reversible, the entropy equation being an exception. Therefore solutions often arise in pairs, one represents forward time and the other reversed time, such as the retarded and advanced solutions of Maxwell's EM equations of EM. Drop a stone in a pond and the wave propagating outwards is represented by the retarded solution, a mathematical advanced solution would represent the wave converging onto the point and time where and when the stone enters the water, it doesn't exist in (our?) reality. [When I have patented my TV that picks up tomorrow's programmes by the advanced tv waves, I'll tell you and enter the lottery!].
    Klauber seems to have done that with the scalar field wave equation.

    Garth
     
    Last edited: Feb 4, 2005
  15. Feb 4, 2005 #14

    selfAdjoint

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    This advanced-retarded wave thing is an old technique. Recall Wheeler and Feynmann did a version of electromagnetism based of it (I believe part of it was Feynmann's PhD thesis). And John Cramer's Transactional Interpretation of QM is based on the same idea with quantum wave functions. The key is that the waves in both directions of time get reflected and come back together and interact, giving physics.
     
  16. Feb 4, 2005 #15

    wolram

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    Enlightenment thanks, i think i will keep this one in the maybe file.
     
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