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Weinberg, Vol. 1: Path Integrals Query

  1. Nov 29, 2007 #1
    I am trying to study QFT from Weinberg's Vol. 1.

    I am at the moment stuck at the path integral quantization of QED (Weinberg's treatment).

    I am not sure how he integrates out the matter field momenta (for the spinor field) in eq. (9.6.5). I thought for spinor fields you don't do that.

    I thought that there should be integration with respect to p_m as given in eq. (9.5.56).

    Any help will be much appreciated.
  2. jcsd
  3. Dec 3, 2007 #2


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    I think he just didn't bother to write [itex]d\psi^\dagger[/itex]. This is essentially a matter of convention as to whether we think of [itex]\psi^\dagger[/itex] as an independent field or not.
  4. Dec 3, 2007 #3
    QFT: Path Integrals, Weinberg Vol. 1

    I had e-mailed SW about this, he told me that it was integrated out.

    My understanding is fairly minimal, but from (9.5.1), (9.5.49) and (9.5.52), I didn't think
    the adjoint spinor could be integrated out. If you could give me a reference, and/or a hint that would be great. I thought one needed equal amounts of \psi and \psi adjoint terms.

    Thanks for your message.
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