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arXiv · 1411.3289

A Cluster Bootstrap for Two-Loop MHV Amplitudes

John Golden·Marcus Spradlin
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Abstract

We apply a bootstrap procedure to two-loop MHV amplitudes in planar N=4 super-Yang-Mills theory. We argue that the mathematically most complicated part (the $Λ^2 B_2$ coproduct component) of the n-particle amplitude is uniquely determined by a simple cluster algebra property together with a few physical constraints (dihedral symmetry, analytic structure, supersymmetry, and well-defined collinear limits). We present a concise, closed-form expression which manifests these properties for all n.

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John Golden, Marcus Spradlin. 2015-01-17. A Cluster Bootstrap for Two-Loop MHV Amplitudes. https://doi.org/10.1007/jhep02(2015)002

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