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Maximal supergravity

  1. Jul 13, 2009 #1
    Provided that no particles have spins higher than 2, maximal supergravities are defined to be with supergravities with 32 supersymmetries.
    Why is the N=8 supergravity in four dimensions called 'the maximal supergravity'? I am confused now....
    Thanks.
     
    Last edited: Jul 14, 2009
  2. jcsd
  3. Jul 13, 2009 #2
    Not an expert, but from what I've been told the N>8 supergravity theories always contain particles with spin > 2. And these are not well-defined.
     
  4. Jul 14, 2009 #3
    Thanks for your reply. However, I am not sure whether it's right.
    Another answer, which may be wrong, is that in four dimensions the spinors are 4-dimensional, then one could obtain 4*8=32 for the N=8 case.
    But what does it mean, and why Is it in accordance with the 32 real supercharges?
     
  5. Jul 15, 2009 #4

    tom.stoer

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    Is there a list of SUGRA theories (in terms of N and D) from which the following information follows
    - particle content
    - chiral structure
    - able to reproduce the standard model (gauge fields, fermion generations, higgs)
    - finiteness (I think there are no rigorous proofs but ongoing research programs)
    - low-energy limit of some string theory
     
    Last edited: Jul 15, 2009
  6. Aug 22, 2009 #5

    tom.stoer

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    I simply ask the same questions a second time - hope somebody will read and provide answers - thanks :-)

     
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