Name: Andreas Ross (email_not_shown)
Date: 08/08/05-11:59:50 PM Z


Hi,

we experienced some problems with the Levi-Civita tensor in the latest version (5 beta1) of FeynCalc which didn't exist in version 4.1.1
If I enter for example

Contract[Eps[LorentzIndex[a], LorentzIndex[b], LorentzIndex[c], LorentzIndex[d]]*FV[p, a]*FV[p + q, b]]

that works in the old version and it throws away the part where p is contracted with two indeces of the Eps tensor.
In the new version however it does not do that. Is there any quick fix for it or can I first use something like
ScalarProductExpand before contracting?

Besides, I found that ScalarProductExpand[FV[p + q, a]] gives different results in version 5 beta1, it does not add the Lorentz index a to both parts as it used to do in version 4.1.1

Unfortunately we need the features of 5 beta1 for our current programs, so is there any way to make FeynCalc 5 beta1 contract the epsilon tensors correctly?

Thank you very much for your help!!!

Andreas



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