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Cosmic quantum measurement

i. c. percival
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Abstract

Hardy's theorem states that the hidden variables of any realistic theory of quantum measurement, whose predictions agree with ordinary quantum theory, must have a preferred Lorentz frame. This presents the conflict between special relativity and any realistic dynamics of quantum measurement in a severe form. The conflict is resolved using a `measurement field', which provides a timelike function of spacetime points and a definition of simultaneity in the context of a curved spacetime. Locally this theory is consistent with special relativity, but globally, special relativity is not enough; the time dilation of general relativity and the standard cosmic time of the Robertson-Walker cosmologies are both essential. A simple but crude example is a relativistic quantum measurement dynamics based on the nonrelativistic measurement dynamics of Lüders.

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i. c. percival. 1998-11-30. Cosmic quantum measurement. https://doi.org/10.1098/rspa.2000.0507

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