Name: manuel J. Vicente Date: 05/06/15-02:38:40 PM Z
Dear Vladyslav,
thanks for your prompt answer. I’ve also found another problem with
OneLoop. It fails in the 8.2.0 and in today’s nightly version. Results
from default options and OneLoopSimplify->True differ.
Notice the first line: bb=k. It corresponds to an external momentum. Changing its name to anything alphabetically after p (e.g. bb=x) seems to solve the problem??
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«FeynCalc`
bb = k;
ScalarProduct[bb, p1] = 0; ScalarProduct[bb, bb] = 0;
ScalarProduct[p1, p1] = m^2; ScalarProduct[p2, p2] =
m^2;
ScalarProduct[p1, r] = 0; ScalarProduct[bb, r] = 0;
ScalarProduct[bb, p2] = 0; ScalarProduct[r, p2] = 1;
ScalarProduct[p1, p2] = 0;
amp = SPD[r, z] SPD[bb, z] SPD[p2, z]
SPD[p1,
z] FAD[{z, 0}, {p1 + bb - z, m}, {p2 - z, m}, {p1 - z,
m}];
FI; OneLoop[z, amp] // PaVeReduce
(-I/24)*m^2*Pi^2
OneLoop[z, amp, OneLoopSimplify -> True]
0
======================================
best regards and thanks again!
M.J. Vicente