Name: Vladyslav Shtabovenko Date: 12/16/14-11:59:30 AM Z
Hi Ralph,
FeynArts and FeynCalc are two different projects developed by
different
people, so there is no 100% comptability between the two. For
practical
purposes one always needs to convert the FeynArts output into
something
FeynCalc can work with.
Have a look at the examples, for more details
https://github.com/FeynCalc/feyncalc/tree/master/FeynCalc/fcexamples/QED
Since you are using FeynCalc 8.2, you don’t need to apply to
FCPrepareFAAmp and specify Transversality->True in
PolarizationVector.
Those are things that came with FeynCalc 9 that is still under
devlopment.
Also, have a look at the corresponding wiki page:
https://github.com/FeynCalc/feyncalc/wiki/FeynArts#fatofc
Cheers,
Vladyslav
On 15/12/14 20:12, Ralph wrote:
> Thanks for the suggestion Vladyslav, turns out FeynArtsDirectory was
set to ./FeynArts-3.7/� and after I changed it seems to load ok.
Is it possible for FC to process the output of FA so that traces are
contracted etc? I tried the following:
>
> t = CreateTopologies[0, 2 ->
2];��������
> ww = InsertFields[t, {F[3], -F[3]} ->
{V[3], -V[3]}];���
> ampww = CreateFeynAmp[ww, Truncated ->
False];��
> tmp2 = Apply[List, ampww] /.
> FeynAmp[_, _, am_, _] :> (am /. RelativeCF -> 1) /.
> Polarization[a_, b_, _] :> Polarization[a, b]
> enmomcon = k2 -> p2 + p1 - k1;
> tmp3 = Explicit[Plus @@ tmp2, Gauge -> (1 -
\[Alpha]),
> Dimension -> 4] /. enmomcon���
>
> Calc[tmp3]
>
> But all the gamma matrices etc are still uncontracted. Is there
something else I should do, or is it not possible to convert the
CreateFeynAmp output into the type of analytical expression you can
usually get in FC?
>