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Gaussian quantum operator representation for bosons

Joel F. Corney·Peter D. Drummond
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Abstract

We introduce the Gaussian quantum operator representation, using the most general multi-mode Gaussian operator basis. The representation unifies and substantially extends existing phase-space representations of density matrices for Bose systems, and also includes generalized squeezed-state and thermal bases. It enables first-principles dynamical or equilibrium calculations in quantum many-body systems, with quantum uncertainties appearing as dynamical objects. Any quadratic Liouville equation for the density operator results in a purely deterministic time evolution. Any cubic or quartic master equation can be treated using stochastic methods.

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Joel F. Corney, Peter D. Drummond. 2003-09-24. Gaussian quantum operator representation for bosons. https://doi.org/10.1103/physreva.68.063822

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