GROUP THEORY FACTORS FOR FEYNMAN DIAGRAMS

Group theory for Feynman diagrams in non-Abelian gauge theories

The increased interest in non-Abelian gauge theories has in recent years led to the computation of many higher-order Feynman diagrams. ' " Asymptotic form-factor and scattering amplitude calculations are of special interest, because they suggest that it might be possible to sum up diagrams with arbitrary numbers of soft gluons just as one can sum up soft-photon processes in QED. In such a progr...

Matrix Theory and Feynman Diagrams

We briefly review the computation of graviton and antisymmetric tensor scattering amplitudes in Matrix Theory from a diagramatic S-Matrix point of view. It is by now commonly believed that eleven dimensional supergravity is the low-energy effective theory of a more fundamental microscopic model, known as M-theory. A proposed definition of M-theory has been given in terms of the large N limit of...

Feynman diagrams in inverse spec- tral theory

Symmetry Factors of Feynman Diagrams for Scalar Fields

The symmetry factor of Feynman diagrams for real and complex scalar fields is presented. Being analysis of Wick expansion for Green functions, the mentioned factor is derived in a general form. The symmetry factor can be separated into two ones corresponding to that of connected and vacuum diagrams. The determination of symmetry factors for the vacuum diagrams is necessary as they play a role i...

A General Expression for Symmetry Factors of Feynman Diagrams

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