Putting a generally valid upper bound on equilibration times of physically relevant observables is a much pursued endeavor. Recently, such a bound has been suggested by Garcia-Pintos et al. While the mathematical correctness of the bound as such is undisputed, its concrete calculation requires the knowledge of certain quantities, which Garcia-Pintos et al. assess by means of assumptions. We show that, e.g., in standard cases of slow, exponential equilibration, (at least) one of these assumptions is not valid. This demonstration highlights the difficulty to judge the validity of the above assumptions without further information. Such information is, in general, very hard to obtain.

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评论“物理相关可观察物的平衡时间尺度”

在物理上相关的可观察物的平衡时间上设置一个通常有效的上限是一个非常追求的工作。最近，Garcia-Pintos等人已经提出了这样的界限。虽然界线的数学正确性是无可争议的，但其具体计算需要了解一定数量的知识，Garcia-Pintos等人。通过假设进行评估。我们证明，例如，在缓慢的，指数均衡的标准情况下，（至少）这些假设之一无效。该演示突显了在没有更多信息的情况下很难判断上述假设的有效性。通常，此类信息很难获得。