Name: Nikita Belyaev Date: 08/03/14-08:38:24 PM Z
Good day,
I’ve tried to calculate some matrix elements and I’ve faced with a
bug.
As an example I can provide the following calculation.
Here are the well-known formula to calculate some trace combinations
(FeynCalc syntaxis):
Tr1a = Tr[P1.P2.P3.GA[i].(1 - GA[5])];
Tr2a = Tr[Q1.Q2.Q3.GA[i].(1 - GA[5])];
Tr3a = Tr[P1.P2.P3.GA[i].Q1.Q2.Q3.GA[i].(1 -
GA[5])];
Result = FullSimplify[Contract[Tr1a.Tr2a + 2 Tr3a]];
P1,…,Q1,… are dirac slashed values.
Result should be zero, but in FeynCalc there is a bug with calculating
of Tr[P1.P2.P3.GA[i].Q1.Q2.Q3.GA[i].GA[5])
term. The result contsins wrong imaginary combination of Levi-Civita
symbols (there are 15 terms instead of 6), real part is zero.
So what is the reason for that?
I can provide any files you might need.
P.S. FeynCalc 8.2.0, Mathematica 9