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arXiv · 1712.08049

Boundaries of Amplituhedra and NMHV Symbol Alphabets at Two Loops

Igor Prlina·Marcus Spradlin·James Stankowicz·Stefan Stanojevic
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Abstract

In this sequel to arXiv:1711.11507 we classify the boundaries of amplituhedra relevant for determining the branch points of general two-loop amplitudes in planar $\mathcal{N}=4$ super-Yang-Mills theory. We explain the connection to on-shell diagrams, which serves as a useful cross-check. We determine the branch points of all two-loop NMHV amplitudes by solving the Landau equations for the relevant configurations and are led thereby to a conjecture for the symbol alphabets of all such amplitudes.

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Igor Prlina, Marcus Spradlin, James Stankowicz, Stefan Stanojevic. 2017-12-21. Boundaries of Amplituhedra and NMHV Symbol Alphabets at Two Loops. https://doi.org/10.1007/jhep04(2018)049

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