本文证明了Strauss等人最近提出的“时间箭头”算子M_F，在arXiv：0802.2448v1 [quant-ph]中，它仅仅与可观测的规范“时间”的符号T有关（显然是由Holevo首先引入的）。特别地，的单调减少< M_F >对应于< sgn T >随时间单调增加的事实。这种关系也提供了性质M_F < 1的物理解释。一些进一步的性质和可能的概括指出，包括几乎周期系统。
英文摘要：
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.
Comment on "Entanglement and the Thermodynamic Arrow of Time" and Correct Reply on "Comment on "Quantum Solution to the Arrow-of-Time Dilemma"" of David Jennings and Terry Rudolph
Comments on `Stable Quantum Computation of Unstable Classical Chaos,' `Efficient Quantum Computing Insensitive to Phase Errors,' and `Quantum Computer Inverting Time Arrow for Macroscopic Systems'
最近，论文B。乔治和D.L. Shepelyansky，Phys. Rev. 86_，5393（2001）中提出的[C. Zalka，quant-ph/0110019; L. Di'osi，quant-ph/0110026]。这封信声称，当在量子计算机上执行Arnold猫映射下的相空间密度演化时，误差敏感性将呈指数级加速和降低。一方面，有些观点以前的答复者尚未提出。另一方面，作者的反应[quant-ph/0110142]提出了新的问题。本说明述及这两个问题。
"New Cybernetics and the Application of its Principles in Physics" and "Comment on "Quantum Solution to the Arrow-of-Time Dilemma" of L. Maccone arXiv:0802.0438"
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