Equilibration of Non-Markovian Quantum Processes in Finite Time Intervals

• URL: http://arxiv.org/abs/2112.01099v2
• Date: Thu, 22 Dec 2022 03:43:58 GMT
• Title: Equilibration of Non-Markovian Quantum Processes in Finite Time Intervals
• Authors: Neil Dowling, Pedro Figueroa-Romero, Felix A. Pollock, Philipp Strasberg, Kavan Modi
• Abstract summary: Quantum processes are shown, within finite time intervals and for finite dimensional time Hamiltonians, to be close to a corresponding stationary equilibrium process. This dictates conditions on time scales at when the multitime statistics of any arbitrary non-equilibrium quantum process look equilibrium on average.
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• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Quantum stochastic processes are shown, within finite time intervals and for finite dimensional time-independent Hamiltonians, to be close to a corresponding stationary equilibrium process. This occurs for multitime observables that are coarse grained in both space and time, and for systems which have many significantly interacting energy eigenstates. This dictates conditions on time scales at when the multitime statistics of any arbitrary non-equilibrium quantum process look equilibrium on average. We show that this leads to the equilibration of general geometric measures of quantum processes, such as the degree of non-Markovianity or classicality. The implications of this result for the emergence of classical stochastic processes from underlying quantum mechanics are also discussed.

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