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arXiv · 1711.11507

All-Helicity Symbol Alphabets from Unwound Amplituhedra

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

We review an algorithm for determining the branch points of general amplitudes in planar $\mathcal{N}=4$ super-Yang-Mills theory from amplituhedra. We demonstrate how to use the recent reformulation of amplituhedra in terms of `sign flips' in order to streamline the application of this algorithm to amplitudes of any helicity. In this way we recover the known branch points of all one-loop amplitudes, and we find an `emergent positivity' on boundaries of amplituhedra.

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Igor Prlina, Marcus Spradlin, James Stankowicz, Stefan Stanojevic, Anastasia Volovich. 2018-05-15. All-Helicity Symbol Alphabets from Unwound Amplituhedra. https://doi.org/10.1007/jhep05(2018)159

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