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RussianTrick

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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.

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Examples

Converted from the *Mathematica* notebook RussianTrick.nb