Hello,
I am having problems running a notebook I have written in FC v9.2 (Mathematica 10) within a PC with FC v9.3 (Mathematica 12).
I have generated tadpole diagrams using FeynArts and I want to have the amplitude expression in FeynCalc form, for that I use:
amps = FCFAConvert[CreateFeynAmp[DiagTadpolesBigH],
IncomingMomenta -> {p}, LoopMomenta -> {q},
UndoChiralSplittings -> True, SMP -> True, DropSumOver -> True,
ChangeDimension -> 4 - \[Epsilon]] /.
PropagatorDenominator[x_, y_] :>
FeynAmpDenominator[PropagatorDenominator[x, y]] /. paramsubs //
Contract
But it doesn't accept the dimension change, it says
ChangeDimension::failmsg: Error! ChangeDimension has encountered a fatal problem and must abort the computation. The problem reads: Unsupported choice of dimension!
If I choose just \[Epsilon] then it doesn't give me any error but it seems the dimention becomes undefined. Also I need to change
PropagatorDenominator[x_, y_] :>
FeynAmpDenominator[PropagatorDenominator[x, y]]
to
PropagatorDenominator[x_, y_] :>
FeynAmpDenominator[PropagatorDenominator[Momentum[x,4-\[Epsilon]], y]]
for the propagator to behave "normally".
Is there any change in this regard with the change of version of FC?
Cheers,
Duarte
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