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arXiv · 2211.16425

Landau Singularities of the 7-Point Ziggurat I

Luke Lippstreu·Marcus Spradlin·Anastasia Volovich
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Abstract

We compute the leading (first-type Landau) singularities of a certain four-loop 7-point graph that is related to the 7-point ``ziggurat'' graph by the graphical moves familiar from equivalent circuit theory. We find perfect agreement with a subset of the ``heptagon symbol alphabet'' that has appeared in the context of planar $\mathcal{N}=4$ super-Yang-Mills theory. The remaining heptagon symbol letters are found in its subleading Landau singularities, which we address in a companion paper.

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Luke Lippstreu, Marcus Spradlin, Anastasia Volovich. 2022-11-29. Landau Singularities of the 7-Point Ziggurat I. https://arxiv.org/abs/2211.16425

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