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arXiv · 1705.05800

New method of computing the contributions of graphs without lepton loops to the electron anomalous magnetic moment in QED

Sergey Volkov
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Abstract

This paper presents a new method of numerical computation of the QED contributions to the electron anomalous magnetic moment which arises from Feynman graphs containing electron and photon lines and not containing electron loops. The method consists of two parts. The first part is the forest-like subtraction formula that removes all ultraviolet and infrared divergences in each Feynman graph point-by-point in Feynman-parametric space. The second part is the importance sampling Monte-Carlo algorithm with the probability density function that is constructed for each Feynman graph individually. The method is fully automated at any order of the perturbation series. The results of applying the method to 2-loop, 3-loop, 4-loop Feynman graphs and to some individual 5-loop graphs are presented.

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Sergey Volkov. 2017-05-16. New method of computing the contributions of graphs without lepton loops to the electron anomalous magnetic moment in QED. https://doi.org/10.1103/physrevd.96.096018

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