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arXiv · 1409.0554

The classical Yang-Baxter equation and the associated Yangian symmetry of gauged WZW-type theories

Georgios Itsios·Konstantinos Sfetsos·Konstantinos Siampos·Alessandro Torrielli
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Abstract

We construct the Lax-pair, the classical monodromy matrix and the corresponding solution of the Yang--Baxter equation, for a two-parameter deformation of the Principal chiral model for a simple group. This deformation includes as a one-parameter subset, a class of integrable gauged WZW-type theories interpolating between the WZW model and the non-Abelian T-dual of the principal chiral model. We derive in full detail the Yangian algebra using two independent methods: by computing the algebra of the non-local charges and alternatively through an expansion of the Maillet brackets for the monodromy matrix. As a byproduct, we also provide a detailed general proof of the Serre relations for the Yangian symmetry.

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Georgios Itsios, Konstantinos Sfetsos, Konstantinos Siampos, Alessandro Torrielli. 2014-12-27. The classical Yang-Baxter equation and the associated Yangian symmetry of gauged WZW-type theories. https://doi.org/10.1016/j.nuclphysb.2014.10.004

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