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arXiv · 1409.0449

Winding vacuum energies in a deformed O(4) sigma model

Vladimir V. Bazhanov·Gleb A. Kotousov·Sergei L. Lukyanov
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Abstract

We consider the problem of calculating the Casimir energies in the winding sectors of Fateev's SS-model, which is an integrable two-parameter deformation of the O(4) non-linear sigma model in two dimensions. This problem lies beyond the scope of all traditional methods of integrable quantum field theory including the thermodynamic Bethe ansatz and non-linear integral equations. Here we propose a solution based on a remarkable correspondence between classical and quantum integrable systems and express the winding energies in terms of certain solutions of the classical sinh-Gordon equation.

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Vladimir V. Bazhanov, Gleb A. Kotousov, Sergei L. Lukyanov. 2014-09-01. Winding vacuum energies in a deformed O(4) sigma model. https://doi.org/10.1016/j.nuclphysb.2014.11.005

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