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DOE OSTI · 1851283

Symbol alphabets from plabic graphs III: n = 9

Mago, J.·Schreiber, A.·Spradlin, M.·Srikant, A. Yelleshpur·Volovich, A.
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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 G(4, n) as well as certain algebraic functions of cluster variables. In this paper we solve the C Z = 0 matrix equations associated to several cells of the totally non-negative Grassmannian, combining methods of arXiv:2012.15812 for rational letters and arXiv:2007.00646 for algebraic letters. We identify sets of parameterizations of the top cell of G + (5, 9) for which the solutions produce all of (and only) the cluster variable letters of the 2-loop nine-particle NMHV amplitude, and identify plabic graphs from which all of its algebraic letters originate.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSPhysicsScattering amplitudesSupersymmetric gauge theory

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Mago, J., Schreiber, A., Spradlin, M., Srikant, A. Yelleshpur, Volovich, A.. 2021-09-01. Symbol alphabets from plabic graphs III: n = 9. https://doi.org/10.1007/jhep09(2021)002

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