RussianTrick

Description

RussianTrick[exp, k, {q1,q2,p}] (=RussianTrick[exp,p,p,{q1,q2,p}]) does the integration by parts where p is the external momentum. RussianTrick[exp, k,l, {q1,q2,p}] (=RussianTrick[exp,k,l]) does integration by parts where l is the momentum to be differentiated.

The result is an expression which is vanishing.

See also:  FourDivergence, FourLaplacian.

Examples

t = RHI[{OPEm, 0,  0, 0,  0},  {1,  1,  1,  1,  1}]

t // RHI2FC

RussianTrick[% // RHI2FC, q2]

FC2RHI[%]

Solve2[%, t]

Clear[t]