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arXiv · 2010.07879

RG flows of integrable $\sigma$-models and the twist function

François Delduc·Sylvain Lacroix·Konstantinos Sfetsos·Konstantinos Siampos
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Abstract

In the study of integrable non-linear $\sigma$-models which are assemblies and/or deformations of principal chiral models and/or WZW models, a rational function called the twist function plays a central role. For a large class of such models, we show that they are one-loop renormalizable, and that the renormalization group flow equations can be written directly in terms of the twist function in a remarkably simple way. The resulting equation appears to have a universal character when the integrable model is characterized by a twist function.

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François Delduc, Sylvain Lacroix, Konstantinos Sfetsos, Konstantinos Siampos. 2020-10-15. RG flows of integrable $\sigma$-models and the twist function. https://doi.org/10.1007/jhep02(2021)065

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