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arXiv · 0802.2682

Comment on "An Arrow of Time Operator for Standard Quantum Mechanics" - a sign of the time!

Michael J. W. Hall
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Abstract

It is shown that the `arrow of time' operator, M_F, recently suggested by Strauss et al., in arXiv:0802.2448v1 [quant-ph], is simply related to the sign of the canonical `time' observable, T (apparently first introduced by Holevo). In particular, the monotonic decrease of < M_F > corresponds to the fact that < sgn T > increases monotonically with time. This relationship also provides a physical interpretation of the property M_F < 1. Some further properties and possible generalisations are pointed out, including to almost-periodic systems.

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Michael J. W. Hall. 2008-02-20. Comment on "An Arrow of Time Operator for Standard Quantum Mechanics" - a sign of the time!. https://arxiv.org/abs/0802.2682

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