Name: Stefano Colucci Date: 06/13/17-04:05:40 PM Z


Hi again,

and thanks for your prompt answer. Regarding the use of “.” : I guess I was mislead by reading in the documentation page for Contract :

” The “.” as multiplication operator is not necessary but just convenient for typesetting.”

Anyways I followed your suggestions but I still get an error message and no result when calling

In[64]:= DiracTrace[AmpF2, DiracTraceEvaluate -> True, West -> True]

During evaluation of In[64]:= DiracTrace::ndranomaly: You are using naive dimensional regularization (NDR), such that in D dimensions gamma^5 anticommutes with all other Dirac matrices. In this scheme (without additional prescriptions) it is not possible to compute traces with an odd number of gamma^5 unambiguously. Evaluation aborted! >>

Out[64]= $Aborted

I have tried to set D->4 before or to use the option West-> True, but no luck so far.

Thanks again for your help,

Stefano