I am learning Mathematica and
FeynCalc by doing some basic cross section calculations.
I have an issue with trace calculations: When I plug in for instance the interference term for
ee->tautau, the result comes out with the
g00 component of the metric tensor explicitly written, i.e. not set to
1 as it should be. This means I have to manually remove it before the next step in the calculation.
I have tried doing something like
MetricTensor[0,0]:=1, but it did not help. I am probably missing some syntax, but can you point me to the correct way of doing it?
Here is my code:
DiracSimplify[ Contract[e^2*gz^2/4/(s*(s - Mz^2 + Mz*Gammaz))/4* Tr[GA[mu].(GS[q2] - M).GA.(cV - cA GA).GA.GA[ nu].(GS[q1] + M)]* Tr[GA[mu].(GS[p1] + m).GA.(cV - cA GA).GA.GA[ nu].(GS[p2] - m)]]];