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arXiv · 1506.05784

Generalised integrable $λ$- and $η$-deformations and their relation

Konstantinos Sfetsos·Konstantinos Siampos·Daniel C. Thompson
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Abstract

We construct two-parameter families of integrable $λ$-deformations of two-dimensional field theories. These interpolate between a CFT (a WZW/gauged WZW model) and the non-Abelian T-dual of a principal chiral model on a group/symmetric coset space. In examples based on the $SU(2)$ WZW model and the $SU(2)/U(1)$ exact coset CFT, we show that these deformations are related to bi-Yang-Baxter generalisations of $η$-deformations via Poisson-Lie T-duality and analytic continuation. We illustrate the quantum behaviour of our models under RG flow. As a byproduct we demonstrate that the bi-Yang-Baxter $σ$-model for a general group is one-loop renormalisable.

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Konstantinos Sfetsos, Konstantinos Siampos, Daniel C. Thompson. 2015-08-31. Generalised integrable $λ$- and $η$-deformations and their relation. https://doi.org/10.1016/j.nuclphysb.2015.08.015

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