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摘要

Paul Davies raises a critical point on the paradoxical arrow of time. Surely, the process of measurement at the quantum level defines a direction of time. Indeed, one could also extend this to note that the discussion about the (theoretical) reversibility of gas mixing is dependent upon perfect knowledge of state, which quantum mechanics also tells us isn't possible. Do these add to define both a direction of time and a link between the classical concept of entropy and the quantum world? As someone who is rooted in thermodynamics, it seems entropy gets short shrift in cosmological ponderings.