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arXiv · 1804.07084

On dual description of the deformed $O(N)$ sigma model

A. V. Litvinov·L. A. Spodyneiko
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Abstract

We study dual strong coupling description of integrability-preserving deformation of the $O(N)$ sigma model. Dual theory is described by a coupled theory of Dirac fermions with four-fermion interaction and bosonic fields with exponential interactions. We claim that both theories share the same integrable structure and coincide as quantum field theories. We construct a solution of Ricci flow equation which behaves in the UV as a free theory perturbed by graviton operators and show that it coincides with the metric of the $\eta-$deformed $O(N)$ sigma-model after $T-$duality transformation.

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A. V. Litvinov, L. A. Spodyneiko. 2018-04-19. On dual description of the deformed $O(N)$ sigma model. https://doi.org/10.1007/jhep11(2018)139

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