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Initial-Value Problem for Inhomogeneous Condensate: Gaussian Approximation and Beyond

Chi-Yong Lin·A. F. R. de Toledo Piza
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Abstract

Using many-body theory we develop a set of formally exact kinetic equations for inhomogeneous condensate and one-body observables. The method is illutrated for phi^4 field theory in 1+1 dimensions. These equations, when computed with the help of time-dependent projection technique, lead to a systematic mean-field expansion. The lowest and the higher order terms correspond to, respectively, the gaussian approximation and the dynamical correlation effect.

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Chi-Yong Lin, A. F. R. de Toledo Piza. 1999-02-02. Initial-Value Problem for Inhomogeneous Condensate: Gaussian Approximation and Beyond. https://arxiv.org/abs/cond-mat/9902027

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