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Description of isolated macroscopic systems inside quantum mechanics

L. Lanz·O. Melsheimer·B. Vacchini
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Abstract

For an isolated macrosystem classical state parameters $ζ(t)$ are introduced inside a quantum mechanical treatment. By a suitable mathematical representation of the actual preparation procedure in the time interval $[T,t_0]$ a statistical operator is constructed as a solution of the Liouville von Neumann equation, exhibiting at time $t$ the state parameters $ζ(t')$, $t_0\leq t' \leq t$, and {\it preparation parameters} related to times $T \leq t'\leq t_0$. Relation with Zubarev's non-equilibrium statistical operator is discussed. A mechanism for memory loss is investigated and time evolution by a semigroup is obtained for a restricted set of relevant observables, slowly varying on a suitable time scale.

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L. Lanz, O. Melsheimer, B. Vacchini. 1999-10-09. Description of isolated macroscopic systems inside quantum mechanics. https://doi.org/10.1016/s0034-4877(01)80023-9

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