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arXiv · 2308.08199

An Eight Loop Amplitude via Antipodal Duality

Lance J. Dixon·Yu-Ting Liu
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Abstract

We compute the six-particle maximally-helicity-violating (MHV) amplitude in planar ${\cal N}=4$ super-Yang-Mills theory at eight loops, using antipodal duality and the recently computed eight-loop three-point form factor for the chiral stress energy tensor multiplet. Antipodal duality maps the form factor symbol to the amplitude symbol on a two-dimensional parity-preserving surface in the three-dimensional amplitude kinematics. There are remarkably few ambiguities in lifting from two to three dimensions, nor in promoting the symbol to a function. The amplitude passes many tests, including near-collinear, multi-Regge, factorization, self-crossing and origin limits. These checks also constitute a validation of antipodal duality at eight loops.

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Lance J. Dixon, Yu-Ting Liu. 2023-08-16. An Eight Loop Amplitude via Antipodal Duality. https://arxiv.org/abs/2308.08199

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