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The time-reversal test for stochastic quantum dynamics

Mark R. Dowling·Peter D. Drummond·Matthew J. Davis·Piotr Deuar
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Abstract

The calculation of quantum dynamics is currently a central issue in theoretical physics, with diverse applications ranging from ultra-cold atomic Bose-Einstein condensates (BEC) to condensed matter, biology, and even astrophysics. Here we demonstrate a conceptually simple method of determining the regime of validity of stochastic simulations of unitary quantum dynamics by employing a time-reversal test. We apply this test to a simulation of the evolution of a quantum anharmonic oscillator with up to $6.022\times10^{23}$ (Avogadro's number) of particles. This system is realisable as a Bose-Einstein condensate in an optical lattice, for which the time-reversal procedure could be implemented experimentally.

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Mark R. Dowling, Peter D. Drummond, Matthew J. Davis, Piotr Deuar. 2004-11-26. The time-reversal test for stochastic quantum dynamics. https://doi.org/10.1103/physrevlett.94.130401

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