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Gravitational self-localization in quantum measurement

Tamas Geszti
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Abstract

Within Newton-Schrödinger quantum mechanics which allows gravitational self-interaction, it is shown that a no-split no-collapse measurement scenario is possible. A macroscopic pointer moves at low acceleration, controlled by the Ehrenfest-averaged force acting on it. That makes classicality self-sustaining, resolves Everett's paradox, and outlines a way to spontaneous emergence of quantum randomness. Numerical estimates indicate that enhanced short-range gravitational forces are needed for the scenario to work. The scheme fails to explain quantum nonlocality, including two-detector anticorrelations, which points towards the need of a nonlocal modification of the Newton-Schrödinger coupling scheme.

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Tamas Geszti. 2004-01-15. Gravitational self-localization in quantum measurement. https://doi.org/10.1103/physreva.69.032110

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