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Stochastic Gross-Pitaevsky Equation for BEC via Coarse-Grained Effective Action

Esteban Calzetta·B. L. Hu·Enric Verdaguer
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Abstract

We sketch the major steps in a functional integral derivation of a new set of Stochastic Gross-Pitaevsky equations (GPE) for a Bose-Einstein condensate (BEC) confined to a trap at zero temperature with the averaged effects of non-condensate modes incorporated as stochastic sources. The closed-time-path (CTP) coarse-grained effective action (CGEA) or the equivalent influence functional method is particularly suitable because it can account for the full back-reaction of the noncondensate modes on the condensate dynamics self-consistently. The Langevin equations derived here containing nonlocal dissipation together with colored and multiplicative noises are useful for a stochastic (as distinguished from say, a kinetic) description of the nonequilibrium dynamics of a BEC. This short paper contains original research results not yet published anywhere.

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Esteban Calzetta, B. L. Hu, Enric Verdaguer. 2007-02-02. Stochastic Gross-Pitaevsky Equation for BEC via Coarse-Grained Effective Action. https://doi.org/10.1142/s0217979207045475

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