Abstract
Abstract
Putting a general, physically relevant upper bound on equilibration times in closed quantum systems is a recently much pursued endeavor. In 2017 Phys. Rev. X 7 031027 García-Pintos et al suggest such a bound. We point out that the general assumptions which allow for an actual estimation of this bound are violated in cases in which Fermi’s golden rule and related open quantum system theories apply. To probe the range of applicability of Fermi’s golden rule for systems of the type addressed in the above work, we numerically solve the corresponding Schrödinger equation for some finite spin systems comprising up to 25 spins. These calculations shed light on the breakdown of standard quantum master equations in the ‘superweak’ coupling limit, which occurs for finite sized baths.
Funder
Deutsche Forschungsgemeinschaft
Subject
General Physics and Astronomy,Mathematical Physics,Modeling and Simulation,Statistics and Probability,Statistical and Nonlinear Physics
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