Description

LorentzIndex[mu] denotes a four dimensional Lorentz index. For other than four dimensions: LorentzIndex[mu, D] or LorentzIndex[mu], etc. LorentzIndex[mu, 4] simplifies to LorentzIndex[mu].

See also: ChangeDimension, Momentum.

Examples

This denotes a four-dimensional Lorentz index.

An optional second argument can be given for a dimension different from 4.

LorentzIndex[ComplexIndex[α]]

Setting $LorentzIndices=True displays the dimension (if different from 4) as a subindex.

The FeynCalc Book

Li3

Map2