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Homework Help: Peskin, Schroeder (2.30)

  1. Aug 15, 2005 #1
    Can someone tell me what the two commutators in (2.30) stand for? It has to be Dirac delta functions, but which one exactly?

    thank you
     
  2. jcsd
  3. Aug 16, 2005 #2

    hellfire

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    Acording to (2.29) the first one should be - [itex]\delta[/itex](p' + p) and the second [itex]\delta[/itex](p + p'). After substracting both the negative sign as well as the factor 2 cancel in (2.30). I guess you should then make use of:

    [tex] \int \delta(p + p^{\prime}) F(p^{\prime}) dp^{\prime} = F(- p) [/tex]

    to obtain the final result in (2.30).
     
  4. Aug 17, 2005 #3
    Thanks hellfire
     
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