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arXiv · 1101.5981

Chinese Magic in Loop Integrals

B. F. L. Ward
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Abstract

We present an approach to higher point loop integrals using Chinese magic in the virtual loop integration variable. We show, using the five point function in the important e^+e^-\to f\bar{f}+γprocess for ISR as a pedagogical vehicle, that we get an expression for it directly reduced to one scalar 5-point function and 4-, 3-, and 2- point integrals, thereby avoiding the computation of the usual three tensor 5-pt Passarino-Veltman reduction. We argue that this offers potential for greater numerical stability.

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B. F. L. Ward. 2011-06-02. Chinese Magic in Loop Integrals. https://doi.org/10.1103/physrevd.83.113014

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