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arXiv · 1707.05149

Integrable flows between exact CFTs

George Georgiou·Konstantinos Sfetsos
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Abstract

We explicitly construct families of integrable $σ$-model actions smoothly interpolating between exact CFTs. In the ultraviolet the theory is the direct product of two current algebras at levels $k_1$ and $k_2$. In the infrared and for the case of two deformation matrices the CFT involves a coset CFT, whereas for a single matrix deformation it is given by the ultraviolet direct product theories but at levels $k_1$ and $k_2-k_1$. For isotropic deformations we demonstrate integrability. In this case we also compute the exact beta-function for the deformation parameters using gravitational methods. This is shown to coincide with previous results obtained using perturbation theory and non-perturbative symmetries.

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George Georgiou, Konstantinos Sfetsos. 2017-11-27. Integrable flows between exact CFTs. https://doi.org/10.1007/jhep11(2017)078

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