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How quantizable matter gravitates

  1. Apr 1, 2015 #1
    Here's a video that claims that gravity can be derived from the Standard Model.
    See the Video.

    The video is by Frederic P Schuller.

    Isn't this exactly what Einstein was trying to accomplish in the last 30 years of his life - to unite EM and GR?

    Or isn't this exactly what quantum gravity would do - derive the metric from the quantum theory of matter?

    If so, I find it absolutely amazing that the speaker does not actually say so.
     
    Last edited: Apr 1, 2015
  2. jcsd
  3. Apr 1, 2015 #2
    He has a book on it here.
     
  4. Apr 2, 2015 #3

    wabbit

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    This looks very interesting but as I gather from a quick look this is about classical (not quantum) theories. "Quantizability" is imposed as a constraint, but the results seem to concern classical description, e.g, he derives Einstein-Hilbert action from Maxwell equations under his assumptions.

    So there doesn't seem to be a QG theory there (yet), though perhaps a possible road towards a QG.

    Would that be a fair asessment?
     
  5. Apr 2, 2015 #4
    Give me some time. I'm going through his video series and will probably have to read his 150 page paper. But from what I can tell, he seems to have accomplished exactly what Einstein was trying to do in the last 30 years of his life - uniting gravity and electromagnetism. I'm surprised not more is made of this accomplishment.
     
  6. Apr 2, 2015 #5

    wabbit

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    Ah yes sorry, yes what he does can be described as "unifying GR and EM" - but my point was that, even with the "quantizable matter" condition this seems a far cry from unifying GR and QM. Also I only looked at the book, not the videos, maybe he went further after the book.
     
  7. Apr 2, 2015 #6
    No, the video does not seem to go into depth on the necessity of quantum theory.

    Perhaps the quantum theory is necessary to get the classical theory to begin with. As I understand it, all these matter theories (EM, weak bosons, quarks, etc) are derived from symmetries of a lagrangian. I seem to remember people saying that you could get all these electrons and quarks by first imposing that the action must have the SU(3)SU(2)U(1) symmetries. Or perhaps, for example, if the Feynman path integral were necessary from first principles, that may be where the minimum action principle comes from to begin with.
     
  8. Apr 2, 2015 #7

    wabbit

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    Possibly yes, but now you've gone way past my limited understanding : )
     
  9. Apr 12, 2015 #8
    The speaker on the video seems to be claiming that GR can be derived from the Standard Model. Isn't this an answer to the search for quantum gravity? And does this allow for gravitational waves, where there is no matter but there is gravity. In other words, is the vacuum energy a sufficient part of the SM to account for gravitational waves by the thesis in the video?

    Again, here is the Video.
     
  10. Apr 12, 2015 #9

    wabbit

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    Is there a paper ? I won't watch a one hour video : )
     
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