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Aspects of Symmetry in Sine-Gordon Theory

Davide Fioravanti
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Abstract

As a prototype of powerful non-abelian symmetry in an Integrable System, I will show the appearance of a Witt algebra of vector fields in the SG theory. This symmetry does not share anything with the well-known Virasoro algebra of the conformal $c=1$ unperturbed limit. Although it is quasi-local in the SG field theory, nevertheless it gives rise to a local action on $N$-soliton solution variables. I will explicitly write the action on special variables, which possess a beautiful geometrical meaning and enter the Form Factor expressions of quantum theory. At the end, I will also give some preliminary hints about the quantisation.

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Davide Fioravanti. 2001-11-30. Aspects of Symmetry in Sine-Gordon Theory. https://arxiv.org/abs/hep-th/0111289

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