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Comment on "Ehrenfest times for classically chaotic systems"

Steven Tomsovic·Eric J. Heller
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Abstract

In a recent Phys. Rev. E Rapid Communication, the authors, Silvestrov and Beenakker, introduce a way to lengthen the Ehrenfest time, $τ$, for fully chaotic systems. We disagree with several statements made in their paper, and address the following points essential to their conclusions: 1) it is not true that all semiclassical approximations for chaotic systems fail at a so-called `logtime', $τ\propto - \ln (\hbar)$, differing only by a numerical coefficient; and 2) the limitation of the semiclassical approximation as expressed in the authors' Eq. (8) is not limited by their argument leading to Eq. (12).

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Steven Tomsovic, Eric J. Heller. 2002-05-29. Comment on "Ehrenfest times for classically chaotic systems". https://doi.org/10.1103/physreve.68.038201

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