Finite volume expectation values in the sine-Gordon model

Arpad Hegedus

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arXiv · 1909.08467

Finite volume expectation values in the sine-Gordon model

Arpad Hegedus

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Abstract

Using the fermionic basis discovered in the 6-vertex model, we derive exact formulas for the expectation values of local operators of the sine-Gordon theory in any eigenstate of the Hamiltonian. We tested our formulas in the pure multi-soliton sector of the theory. In the ultraviolet limit, we checked our results against Liouville 3-point functions, while in the infrared limit, we evaluated our formulas in the semi-classical limit and compared them upto 2-particle contributions against the semi-classical limit of the previously conjectured LeClair-Mussardo type formula. Complete agreement was found in both cases.

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Arpad Hegedus. 2019-09-18. Finite volume expectation values in the sine-Gordon model. https://arxiv.org/abs/1909.08467

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