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Wigner Centennial: His Function, and Its Environmental Decoherence

Lajos Diosi
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Abstract

In 1983, Wigner outlined a modified Schrödinger--von-Neumann equation of motion for macroobjects, to describe their typical coupling to the environment. This equation has become a principal model of environmental decoherence which is beleived responsible for the emergence ofclassicality in macroscopic quantum systems. Typically, this happens gradually and asymptotically after a certain characteristic decoherence time. For the Wigner-function, however, one can prove that it evolves perfectly into a classical (non-negative) phase space distribution after a finite time of decoherence.

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Lajos Diosi. 2002-12-17. Wigner Centennial: His Function, and Its Environmental Decoherence. https://arxiv.org/abs/quant-ph/0212103

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