PauliTrace
PauliTrace[exp]
is the head of Pauli traces. By default the trace is not evaluated. The evaluation occurs only when the option PauliTraceEvaluate
is set to True
. It is recommended to use PauliSimplify
, which will automatically evaluate all Pauli traces in the input expression.
See also
Overview, PauliSimplify.
Examples
PauliTrace[CSI[i, j, k, l]]
tr(σi.σj.σk.σl)
PauliTrace[CSI[i, j, k, l], PauliTraceEvaluate -> True]
2(δˉilδˉjk−δˉikδˉjl+δˉijδˉkl)
PauliTrace[CSI[i, j, k, l]]
% // PauliSimplify
tr(σi.σj.σk.σl)
2δˉilδˉjk−2δˉikδˉjl+2δˉijδˉkl