DiracGammaExpand

Description

DiracGammaExpand[exp] expands all DiracGamma[Momentum[a+b+..]] in exp into (DiracGamma[Momentum[a]] + DiracGamma[Momentum[b]] + ...).

See also:  DiracGamma, DiracGammaCombine, DiracMatrix, DiracSimplify, DiracSlash, DiracTrick.

Examples

t = 
      DiracGamma[Momentum[q]]  .  DiracGamma[Momentum[p - q]]

Momentum is the head of p-q, i.e., it is treated as one four-momentum.

StandardForm[t]

With DiracGammaExpand the Momentum[p-q] gets expanded.

DiracGammaExpand[t]

The inverse operation is DiracGammaCombine.

StandardForm[DiracGammaCombine[DiracGammaExpand[t]]]

StandardForm[DiracGammaExpand[t]]

In order to do non-commutative expansion use DiracSimplify.

DiracSimplify[t]

Clear[t]