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arXiv · 1902.11286

The Sklyanin Bracket and Cluster Adjacency at All Multiplicity

John Golden·Andrew J. McLeod·Marcus Spradlin·Anastasia Volovich
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Abstract

We argue that the Sklyanin Poisson bracket on Gr(4,n) can be used to efficiently test whether an amplitude in planar ${\cal{N}}=4$ supersymmetric Yang-Mills theory satisfies cluster adjacency. We use this test to show that cluster adjacency is satisfied by all one- and two-loop MHV amplitudes in this theory, once suitably regulated. Using this technique we also demonstrate that cluster adjacency implies the extended Steinmann relations at all particle multiplicities.

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John Golden, Andrew J. McLeod, Marcus Spradlin, Anastasia Volovich. 2019-02-28. The Sklyanin Bracket and Cluster Adjacency at All Multiplicity. https://doi.org/10.1007/jhep03(2019)195

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