Hi Vladislav,
Thanks for the response, in this particular case it works.
But if I add two gamma matrixes to the formula
Tr1a = Tr[GS[P1].GS[P2].GS[P3].GS[P4].GS[P5].GA[i].(1 - GA[5])];
Tr2a = Tr[GS[Q1].GS[Q2].GS[Q3].GS[Q4].GS[Q5].GA[i].(1 - GA[5])];
Tr3a = Tr[GS[P1].GS[P2].GS[P3].GS[P4].GS[P5].GA[i].GS[Q1].GS[Q2].GS[Q3].GS[Q4].GS[Q5].GA[i].(1 - GA[5])];
Result = Simplify[Contract[Tr1a.Tr2a + 2 Tr3a]] // Schouten
the result is non zero again.
The source of my concern is the following matrix element
Tr1e = Tr[GA[i].(GS[p2] - m).GA[k].(GS[p1] + m)];
Tr2e = Tr[(GS[p] - m).GA[k].(GS[p] + GS[p1] + GS[p2] -
m).GA[l].GS[k2].GA[m].(1 - GA[5])];
Tr3e = Tr[
GS[k1].GA[l].(GS[q] - u).(1 + GA[5].GS[s]).GA[i].(GS[q] -
GS[p1] - GS[p2] - u).GA[m].(1 - GA[5])];
Tr4e = Tr[(GS[p] + GS[p1] + GS[p2] - m).GA[i].(GS[p] -
m).GA[l].GS[k2].GA[m].(1 - GA[5])];
Tr5e = Tr[
GS[k1].GA[l].(GS[q] - GS[p1] - GS[p2] - u).GA[k].(GS[q] -
u).(1 + GA[5].GS[s]).GA[m].(1 - GA[5])];
TrA1A2 = Simplify[Contract[Tr1e.(Tr2e.Tr3e + Tr4e.Tr5e)]] // Schouten
which again contains imaginary part while it should be real.
Is there some rules I have to follow when calculating terms with a lot of gamma matrixes to get a correct result?
Best Regards,
Nikita Belyaev
This archive was generated by hypermail 2b29 : 09/04/20-12:55:05 AM Z CEST