FCClearScalarProducts[] removes all user-performed
specific settings for ScalarProduct’s.
Overview, ScalarProduct, Pair, SP, SPD.
ScalarProduct[p, p] = m^2;
Pair[Momentum[p], Momentum[p]]m^2
FCClearScalarProducts[]
Pair[Momentum[p], Momentum[p]]
SP[p, p]\overline{p}^2
\overline{p}^2