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arXiv · 1407.2853

Nonsinglet pentagons and NMHV amplitudes

A. V. Belitsky
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Abstract

Scattering amplitudes in maximally supersymmetric gauge theory receive a dual description in terms of the expectation value of the super Wilson loop stretched on a null polygonal contour. This makes the analysis amenable to nonperturbative techniques. Presently, we elaborate on a refined form of the operator product expansion in terms of pentagon transitions to compute twist-two contributions to NMHV amplitudes. To start with, we provide a novel derivation of scattering matrices starting from Baxter equations for flux-tube excitations propagating on magnon background. We propose bootstrap equations obeyed by pentagon form factors with nonsinglet quantum numbers with respected to the R-symmetry group and provide solutions to them to all orders in 't Hooft coupling. These are then successfully confronted against available perturbative calculations for NMHV amplitudes to three-loop order.

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A. V. Belitsky. 2015-05-21. Nonsinglet pentagons and NMHV amplitudes. https://doi.org/10.1016/j.nuclphysb.2015.05.002

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