Description

FeynRule[lag, {fields}] derives the Feynman rule corresponding to the field configuration fields of the lagrangian lag.

FeynRule does not calculate propagator Feynman rules.

The option ZeroMomentumInsertion can be used for twist-2 and higher twist operators.

See also: Lagrangian.

Examples

2-gluon Feynman rules (unpolarized)

2-gluon Feynman rules (polarized)

Compare with the Feynman rule tabulated in Twist2GluonOperator.

quark-quark Feynman rule (unpolarized)

quark-quark -gluon-gluon Feynman rule (unpolarized)

In general equality can be shown by Timing[Factor2[ FCE[Calc[ChangeDimension[FCE[OPESumExplicit[n4-t4]],4]/.s->-p-q-r]]]] but it is a little bit slow ...

QCD vertices

The FeynCalc Book

FeynCalcInternal

FieldStrength