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arXiv · 2501.18458

Asymptotics in the bi-Yang-Baxter Sigma Model

Meer Ashwinkumar·Domenico Orlando·Susanne Reffert·Giacomo Sberveglieri
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Abstract

Working in a sector of large charge is a powerful tool to analytically access models that are either strongly coupled or otherwise difficult to solve explicitly. In the context of integrable systems, Volin's method is exactly such a large-charge approach. In this note, we apply this method to the bi-Yang-Baxter deformed $SU(2)$ principal chiral model. Our main result is an explicit expression for the free energy density as an asymptotic expansion. We moreover determine the leading non-perturbative effects both via analytic methods and a resurgence analysis.

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Meer Ashwinkumar, Domenico Orlando, Susanne Reffert, Giacomo Sberveglieri. 2025-01-30. Asymptotics in the bi-Yang-Baxter Sigma Model. https://doi.org/10.1103/rxks-rk37

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