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No Time Asymmetry from Quantum Mechanics

Don N. Page
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Abstract

With CPT-invariant initial conditions that commute with CPT-invariant final conditions, the respective probabilities (when defined) of a set of histories and its CPT reverse are equal, giving a CPT-symmetric universe. This leads me to question whether the asymmetry of the Gell-Mann--Hartle decoherence functional for ordinary quantum mechanics should be interpreted as an asymmetry of {\it time} .

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Don N. Page. 1993-04-19. No Time Asymmetry from Quantum Mechanics. https://doi.org/10.1103/physrevlett.70.4034

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