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arXiv · hep-th/9905214

Integrable Marginal Points in the N-Cosine Model

Bogomil Gerganov
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Abstract

The integrability of the N-cosine model, a N-field generalization of the sine-Gordon model, is investigated. We establish to first order in conformal perturbation theory that, for arbitrary N, the model possesses a quantum conserved current of Lorentz spin 3 on a submanifold of the parameter space where the interaction becomes marginal. The integrability of the model on this submanifold is further studied using renormalization techniques. It is shown that for N = 2, 3, and 4 there exist special points on the marginal manifold at which the N-cosine model is equivalent to models of Gross-Neveu type and therefore is integrable. In the 2-field case we further argue that the points mentioned above exhaust all integrable cases on the marginal submanifold.

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Bogomil Gerganov. 1999-05-27. Integrable Marginal Points in the N-Cosine Model. https://doi.org/10.1016/s0550-3213(99)00677-x

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