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arXiv:gr-qc/0006012 · International Journal of Theoretical Physics

Functional Approach to Quantum Decoherence and the Classical Final Limit: The Mott and Cosmological Problems

Mario Castagnino, Roberto Laura

Published Jul 1, 2000• 40 citations
arXivHTMLPDF
DOI
10.1023/a:1003681328934

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We study the classical limit of quantum mechanics as applied to quantum cosmology. Conventional wisdom regards the peaking of the Wigner function of the Universe around a classical trajectory as being a quantum prediction of that trajectory. We show that, with quantum interference correctly taken into account, the hoped for "classical correlation" does not exist. There are, therefore, serious difficulties with the notion that a pure quantum state has a classical limit relevant to the description of our world. Some form of quantum decoherence appears necessary for a strict classical limit to exist. This alternative is briefly discussed.