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arXiv · 1006.4797

Modern Summation Methods and the Computation of 2- and 3-loop Feynman Diagrams

J. Ablinger·J. Blümlein·S. Klein·C. Schneider
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Abstract

By symbolic summation methods based on difference fields we present a general strategy that transforms definite multi-sums, e.g., in terms of hypergeometric terms and harmonic sums, to indefinite nested sums and products. We succeeded in this task with all our concrete calculations of 2--loop and 3--loop massive single scale Feynman diagrams with local operator insertion.

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J. Ablinger, J. Blümlein, S. Klein, C. Schneider. 2010-06-24. Modern Summation Methods and the Computation of 2- and 3-loop Feynman Diagrams. https://doi.org/10.1016/j.nuclphysbps.2010.08.028

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