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arXiv · 1612.05012

A new class of integrable deformations of CFTs

George Georgiou·Konstantinos Sfetsos
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Abstract

We construct a new class of integrable $σ$-models based on current algebra theories for a general semisimple group $G$ by utilizing a left-right asymmetric gauging. Their action can be thought of as the all-loop effective action of two independent WZW models for $G$ both at level $k$, perturbed by current bilinears mixing the different WZW models. A non-perturbative symmetry in the couplings parametric space is revealed. We perform the Hamiltonian analysis of the action and demonstrate integrability in several cases. We extend our construction to deformations of $G/H$ CFTs and show integrability when $G/H$ is a symmetric space. Our method resembles that used for constructing the $λ$-deformed integrable $σ$-models, but the results are distinct and novel.

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George Georgiou, Konstantinos Sfetsos. 2017-03-21. A new class of integrable deformations of CFTs. https://doi.org/10.1007/jhep03(2017)083

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