DiracChainJoin[exp]
joins chains of Dirac matrices with explicit Dirac indices wrapped with a head DiracChain
. Notice that DiracChainJoin
is not suitable for creating closed Dirac chains out of the FeynArts output with explicit Dirac indices, e.g. when the model contains 4-fermion operators. Use FCFADiracChainJoin
for that.
Overview, DiracChain, DCHN, DiracIndex, DiracIndexDelta, DIDelta, DiracChainCombine, DiracChainExpand, DiracChainFactor, FCFADiracChainJoin.
[SpinorUBar[p1, m1], i] DCHN[GAD[\[Mu]] . GAD[\[Nu]], i, j] DCHN[j, SpinorV[p2, m2]]
DCHN
[%] DiracChainJoin