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arXiv · 2101.01232

Open Fishchain in N=4 Supersymmetric Yang-Mills Theory

Nikolay Gromov·Julius Julius·Nicolo Primi
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Abstract

We consider a cusped Wilson line with J insertions of scalar fields in N=4 SYM and prove that in a certain limit the Feynman graphs are integrable to all loop orders. We identify the integrable system as a quantum fishchain with open boundary conditions. The existence of the boundary degrees of freedom results in the boundary reflection operator acting non-trivially on the physical space. We derive the Baxter equation for Q-functions and provide the quantisation condition for the spectrum. This allows us to find the non-perturbative spectrum numerically.

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Nikolay Gromov, Julius Julius, Nicolo Primi. 2021-01-04. Open Fishchain in N=4 Supersymmetric Yang-Mills Theory. https://doi.org/10.1007/jhep07(2021)127

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