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arXiv · 2110.05418

On loop corrections to integrable $2D$ sigma model backgrounds

Mikhail Alfimov·Alexey Litvinov
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Abstract

We study regularization scheme dependence of $\beta$-function for sigma models with two-dimensional target space. Working within four-loop approximation, we conjecture the scheme in which the $\beta$-function retains only two tensor structures up to certain terms containing $\zeta_3$. Using this scheme, we provide explicit solutions to RG flow equation corresponding to Yang-Baxter- and $\lambda$-deformed $SU(2)/U(1)$ sigma models, for which these terms disappear.

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Mikhail Alfimov, Alexey Litvinov. 2021-10-11. On loop corrections to integrable $2D$ sigma model backgrounds. https://doi.org/10.1007/jhep01(2022)043

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