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arXiv · 1610.03818

Arrow of Time for Continuous Quantum Measurement

Justin Dressel·Areeya Chantasri·Andrew N. Jordan·Alexander N. Korotkov
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Abstract

We investigate the statistical arrow of time for a quantum system being monitored by a sequence of measurements. For a continuous qubit measurement example, we demonstrate that time-reversed evolution is always physically possible, provided that the measurement record is also negated. Despite this restoration of dynamical reversibility, a statistical arrow of time emerges, and may be quantified by the log-likelihood difference between forward and backward propagation hypotheses. We then show that such reversibility is a universal feature of non-projective measurements, with forward or backward Janus measurement sequences that are time-reversed inverses of each other.

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Justin Dressel, Areeya Chantasri, Andrew N. Jordan, Alexander N. Korotkov. 2016-10-12. Arrow of Time for Continuous Quantum Measurement. https://doi.org/10.1103/physrevlett.119.220507

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