Name: Vladyslav Shtabovenko (email_not_shown)
Date: 08/13/15-07:36:40 PM Z


In FeynCalc 9.0 it works out of the box

Contract[TensorFunction[t, a, b] FV[p, b]];
Uncontract[%, p, Pair -> All]

-> Pair[LorentzIndex[$AL$2154[1]], Momentum[p]] t[LorentzIndex[a],
  LorentzIndex[$AL$2154[1]]]

Cheers,
Vladyslav

>
>
> Hello,
>
> is there some way to uncontract indices in tensor functions? Uncontract with Pair->All seems to only work for scalar products of vectors. Here is an example:
>
> Contract[TensorFunction[t, a, b] FV[p, b]];
> Uncontract[%, p, Pair -> All]
>
> gives t(a,p). I did not find a way to separate the tensor from the vector once they are contracted unless I explicitly perform a replacement on the full form, something like:
>
> t[LorentzIndex[a_],Momentum[p_]]->TensorFunction[t,a,b]FV[p,b]
>
> Is there some more straightforward and systematic way to do this?
> Thanks!
>
> Tomas Brauner



This archive was generated by hypermail 2b29 : 03/23/17-07:00:03 AM Z CET