A General Expression for Symmetry Factors of Feynman Diagrams
نویسنده
چکیده
The calculation of the symmetry factor corresponding to a given Feynman diagram is well known to be a tedious problem. We have derived a simple formula for these symmetry factors. Our formula works for any diagram in scalar theory (φ3 and φ4 interactions), spinor QED, scalar QED, or QCD. PACS numbers:11.10.-z, 11.15.-q, 11.15.Bt Typeset using REVTEX 1
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تاریخ انتشار 2001