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arXiv · hep-th/9612252

Completely Integrable Equation for the Quantum Correlation Function of Nonlinear Schrödinger Eqaution

T. Kojima·V. Korepin·N. Slavnov
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Abstract

Correlation functions of exactly solvable models can be described by differential equation [Barough, McCoy, Wu]. In this paper we show that for non free fermionic case differential equations should be replaced by integro-differential equations. We derive an integro-differential equation, which describes time and temperature dependent correlation function $<ψ(0,0)ψ^\dagger(x,t)>_T$ of penetrable Bose gas. The integro-differential equation turns out be the continuum generalization of classical nonlinear Schrödinger equation.

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T. Kojima, V. Korepin, N. Slavnov. 1997-03-26. Completely Integrable Equation for the Quantum Correlation Function of Nonlinear Schrödinger Eqaution. https://doi.org/10.1007/s002200050226

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