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arXiv · 2012.15812

Symbol Alphabets from Plabic Graphs II: Rational Letters

Jorge Mago·Anders Schreiber·Marcus Spradlin·Akshay Yelleshpur Srikant·Anastasia Volovich
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Abstract

Symbol alphabets of n-particle amplitudes in N=4 super-Yang-Mills theory are known to contain certain cluster variables of Gr(4,n) as well as certain algebraic functions of cluster variables. The first paper arXiv:2007.00646 in this series focused on n=8 algebraic letters. In this paper we show that it is possible to obtain all rational symbol letters (in fact all cluster variables) by solving matrix equations of the form C Z = 0 if one allows C to be an arbitrary cluster parameterization of the top cell of Gr_+(n-4,n).

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Jorge Mago, Anders Schreiber, Marcus Spradlin, Akshay Yelleshpur Srikant, Anastasia Volovich. 2020-12-31. Symbol Alphabets from Plabic Graphs II: Rational Letters. https://doi.org/10.1007/jhep04(2021)056

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