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Quantum dynamics with stochastic gauge simulations

P. D. Drummond·P. Deuar
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Abstract

The general idea of a stochastic gauge representation is introduced and compared with more traditional phase-space expansions, like the Wigner expansion. Stochastic gauges can be used to obtain an infinite class of positive-definite stochastic time-evolution equations, equivalent to master equations, for many systems including quantum time-evolution. The method is illustrated with a variety of simple examples ranging from astrophysical molecular hydrogen production, through to the topical problem of Bose-Einstein condensation in an optical trap and the resulting quantum dynamics.

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P. D. Drummond, P. Deuar. 2003-09-23. Quantum dynamics with stochastic gauge simulations. https://doi.org/10.1088/1464-4266%2F5%2F3%2F359

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