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arXiv · 0709.1769

Feynman integrals and difference equations

S. Moch·C. Schneider
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Abstract

We report on the calculation of multi-loop Feynman integrals for single-scale problems by means of difference equations in Mellin space. The solution to these difference equations in terms of harmonic sums can be constructed algorithmically over difference fields, the so-called Pi-Sigma-fields. We test the implementaion of the Mathematica package Sigma on examples from recent higher order perturbative calculations in Quantum Chromodynamics.

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S. Moch, C. Schneider. 2007-09-12. Feynman integrals and difference equations. https://arxiv.org/abs/0709.1769

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