FeynCalc manual (development version)

ScalarProductCancel

ScalarProductCancel[exp, q1, q2, ...] cancels scalar products with propagators.

ScalarProductCancel[exp] cancels simple cases.

ScalarProductCancel is deprecated, please use the more powerful ApartFF instead.

See also

Overview, ApartFF, FCClearScalarProducts, ExpandScalarProduct, Pair, SP, SPC, SPD.

Examples

SPD[q, p] FAD[{q, m}, {q - p, 0}] 
 
ScalarProductCancel[%, q]

\frac{p\cdot q}{\left(q^2-m^2\right).(q-p)^2}

\frac{m^2+p^2}{2 q^2.\left((q-p)^2-m^2\right)}-\frac{1}{2 \left(q^2-m^2\right)}

SPD[q2, p] SPD[q1, p] FAD[{q1, m}, {q2, m}, q1 - p, q2 - p, q2 - q1] //FCI 
 
SPC[%, q1, q2, FDS -> True]

\frac{(p\cdot \;\text{q1}) (p\cdot \;\text{q2})}{\left(\text{q1}^2-m^2\right).\left(\text{q2}^2-m^2\right).(\text{q1}-p)^2.(\text{q2}-p)^2.(\text{q2}-\text{q1})^2}

\frac{\left(m^2+p^2\right)^2}{4 \left(\text{q1}^2-m^2\right).\left(\text{q2}^2-m^2\right).(\text{q1}-p)^2.(\text{q1}-\text{q2})^2.(\text{q2}-p)^2}+\frac{m^2+p^2}{2 \;\text{q1}^2.\text{q2}^2.\left((\text{q1}-p)^2-m^2\right).(\text{q1}-\text{q2})^2}-\frac{m^2+p^2}{2 \left(\text{q1}^2-m^2\right).\left(\text{q2}^2-m^2\right).(\text{q1}-p)^2.(\text{q1}-\text{q2})^2}-\frac{1}{2 \left(\text{q1}^2-m^2\right).(\text{q1}-\text{q2})^2.(\text{q2}-p)^2}+\frac{1}{4 \left(\text{q1}^2-m^2\right).\left(\text{q2}^2-m^2\right).(\text{q1}-\text{q2})^2}