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arXiv · 1311.3342

Schouten identities for Feynman graph amplitudes; the Master Integrals for the two-loop massive sunrise graph

Ettore Remiddi·Lorenzo Tancredi
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Abstract

A new class of identities for Feynman graph amplitudes, dubbed Schouten identities, valid at fixed integer value of the dimension d is proposed. The identities are then used in the case of the two loop sunrise graph with arbitrary masses for recovering the second order differential equation for the scalar amplitude in d=2 dimensions, as well as a chained sets of equations for all the coefficients of the expansions in (d-2). The shift from $d\approx2$ to $d\approx4$ dimensions is then discussed.

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Ettore Remiddi, Lorenzo Tancredi. 2014-01-28. Schouten identities for Feynman graph amplitudes; the Master Integrals for the two-loop massive sunrise graph. https://doi.org/10.1016/j.nuclphysb.2014.01.009

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