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[Req]Help finding equation

  1. Feb 16, 2010 #1
    In the TV Show Seeing Black Holes, from the Science Channel professor Michio Kaku speaks about an equation to formulate general relativity into a quantum field theory witch leads to a infinite sequence of inifinities

    i would like to see that equation if possible.

    i tried google, but no luck so far

    thank you for any help

  2. jcsd
  3. Feb 16, 2010 #2
    Hi kazparov!

    In his book "Quantum Field theory - a modern introduction" there's a chapter on Quantum Gravity. If you don't know where to find the book, just send me a PM.

    best regards, Martin
  4. Feb 16, 2010 #3
    I guess he refers to the fact that a quantum field theory of gravity would be non-renormalizeable. This can be easiliy seen from the dimension of the coupling. If one tries to quantize the classical field theory of gravity (General relativity), one faces the problem that the coupling constant (G in Newton's law), the gravitational constant, has negative mass dimension. Therefore the theory is non-renormalizeable.
    Actually the chapter in his book is quite interesting, unfortunately I don't have the time to read it. In chapter 19.10 he discusses why non-renormalizeabilty is not a problem in principle. He says: "although quantum gravity is formally nonrenormalizebale, we can still hope that (by a series of miracles) the divergences of the quantum loops cancel, leaving us with a finite theory".

    I hope you find answers to your questions in his book (which is really a good one!).
  5. Feb 16, 2010 #4
    Hello, thank you very much for your reply

    Does the book have the equation?, i just want to have a look at the equation

    Thank you

  6. Feb 16, 2010 #5
    You might be looking for Wheeler–DeWitt equation
  7. Feb 16, 2010 #6
    As far as I know there is no settled theory of Quantum Gravity so far. However, there are proposals.
    One of these proposals, as far as I understood Kaku, is a supersymmetric theory, so called "super-gravity".
    He states the Lagrangian in chapter 20, I attached it.

    Best regards

    Attached Files:

  8. Feb 16, 2010 #7
    thank you very much

    and thank you LostConjugate

    both of your replies have been very helpful

    much appreciated
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