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Condensates beyond mean field theory: quantum backreaction as decoherence

Amichay Vardi·James R. Anglin
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Abstract

We propose an experiment to measure the slow log(N) convergence to mean-field theory (MFT) around a dynamical instability. Using a density matrix formalism, we derive equations of motion which go beyond MFT and provide accurate predictions for the quantum break-time. The leading quantum corrections appear as decoherence of the reduced single-particle quantum state.

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Amichay Vardi, James R. Anglin. 2000-07-17. Condensates beyond mean field theory: quantum backreaction as decoherence. https://doi.org/10.1103/physrevlett.86.568

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