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arXiv · 1311.4696

A deformation of quantum affine algebra in squashed WZNW models

Io Kawaguchi·Kentaroh Yoshida
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Abstract

We proceed to study infinite-dimensional symmetries in two-dimensional squashed Wess-Zumino-Novikov-Witten (WZNW) models at the classical level. The target space is given by squashed S^3 and the isometry is SU(2)_L x U(1)_R. It is known that SU(2)_L is enhanced to a couple of Yangians. We reveal here that an infinite-dimensional extension of U(1)_R is a deformation of quantum affine algebra, where a new deformation parameter is provided with the coefficient of the Wess-Zumino term. Then we consider the relation between the deformed quantum affine algebra and the pair of Yangians from the viewpoint of the left-right duality of monodromy matrices. The integrable structure is also discussed by computing the r/s-matrices that satisfy the extended classical Yang-Baxter equation. Finally two degenerate limits are discussed.

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Io Kawaguchi, Kentaroh Yoshida. 2013-11-19. A deformation of quantum affine algebra in squashed WZNW models. https://doi.org/10.1063/1.4880341

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