Name: Manuel J. Vicente Date: 05/05/15-06:21:57 PM Z


I obtain different results with/without the OneLoopSimplify option in the following case:

«FeynCalc`
ScalarProduct[p1, p1] = m^2; ScalarProduct[p2, p2] = m^2;
ScalarProduct[p3, p3] = 0; ScalarProduct[p1, r] = 0;
ScalarProduct[p3, r] = 0; ScalarProduct[p2, r] = 1;
ScalarProduct[p3, p1] = 0; ScalarProduct[p3, p2] = 0;

num = (D - 4) SPD[r, z] SPD[p3, z] SPD[p2, z] SPD[p1, z];

den = FAD[{z, 0}, {p1 + p3 - z, m}, {p2 - z, m}, {p1 - z, m}];

resOLdefault = OneLoop[z, num den]

   ((3*I)/8)*m^2*Pi^2

resOLOLSimplify = OneLoop[z, num den, OneLoopSimplify -> True]

   0
=================
 Could somebody help with this?
   Thanks

M.J. Vicente