FeynCalc manual (development version)

GA

GA[mu] can be used as input for a 4-dimensional \gamma^{\mu } and is transformed into DiracGamma[LorentzIndex[mu]] by FeynCalcInternal (=FCI).

GA[mu , nu , ...] is a short form for GA[mu].GA[nu].

See also

Overview, DiracGamma, GAD, GS.

Examples

GA[\[Mu]]

\bar{\gamma }^{\mu }

GA[\[Mu], \[Nu]] - GA[\[Nu], \[Mu]]

\bar{\gamma }^{\mu }.\bar{\gamma }^{\nu }-\bar{\gamma }^{\nu }.\bar{\gamma }^{\mu }

StandardForm[FCI[GA[\[Mu]]]]

(*DiracGamma[LorentzIndex[\[Mu]]]*)

GA[\[Mu], \[Nu], \[Rho], \[Sigma]]

\bar{\gamma }^{\mu }.\bar{\gamma }^{\nu }.\bar{\gamma }^{\rho }.\bar{\gamma }^{\sigma }

StandardForm[GA[\[Mu], \[Nu], \[Rho], \[Sigma]]]

(*GA[\[Mu]] . GA[\[Nu]] . GA[\[Rho]] . GA[\[Sigma]]*)

GA[\[Alpha]] . (GS[p] + m) . GA[\[Beta]]

\bar{\gamma }^{\alpha }.\left(\bar{\gamma }\cdot \overline{p}+m\right).\bar{\gamma }^{\beta }