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arXiv · hep-th/9512090

Determinant representation for a quantum correlation function of the lattice sine-Gordon model

Fabian H. L. Essler·Holger Frahm·Alexander R. Its·Vladimir E. Korepin
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Abstract

We consider a completely integrable lattice regularization of the sine-Gordon model with discrete space and continuous time. We derive a determinant representation for a correlation function which in the continuum limit turns into the correlation function of local fields. The determinant is then embedded into a system of integrable integro-differential equations. The leading asymptotic behaviour of the correlation function is described in terms of the solution of a Riemann Hilbert Problem (RHP) related to the system of integro-differential equations. The leading term in the asymptotical decomposition of the solution of the RHP is obtained.

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Fabian H. L. Essler, Holger Frahm, Alexander R. Its, Vladimir E. Korepin. 1996-08-08. Determinant representation for a quantum correlation function of the lattice sine-Gordon model. https://doi.org/10.1088/0305-4470%2F30%2F1%2F016

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