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arXiv · hep-th/9512030

Lagrangian Formulation of Symmetric Space sine-Gordon Models

I. Bakas·Q-Han Park·H. J. Shin
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Abstract

The symmetric space sine-Gordon models arise by conformal reduction of ordinary 2-dim $σ$-models, and they are integrable exhibiting a black-hole type metric in target space. We provide a Lagrangian formulation of these systems by considering a triplet of Lie groups $F \supset G \supset H$. We show that for every symmetric space $F/G$, the generalized sine-Gordon models can be derived from the $G/H$ WZW action, plus a potential term that is algebraically specified. Thus, the symmetric space sine-Gordon models describe certain integrable perturbations of coset conformal field theories at the classical level. We also briefly discuss their vacuum structure, Backlund transformations, and soliton solutions.

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I. Bakas, Q-Han Park, H. J. Shin. 1995-12-06. Lagrangian Formulation of Symmetric Space sine-Gordon Models. https://doi.org/10.1016/0370-2693(96)00026-3

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