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arXiv · 1909.01798

Q-functions as models of physical reality

Peter D. Drummond·Margaret D. Reid
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Abstract

We show that one may interpret physical reality as random fields in space-time. These have a probability given by the expectation of a coherent state projection operator, called the Q-function. The resulting dynamical evolution includes retrocausal effects. This suggests that a physical universe exists without requiring observers, but with a well-defined probability for its field configuration. By including the meter dynamics, we show that field trajectories have quantum measurement properties without wave-function collapse, including sharp measured eigenvalues. We treat continuous and discrete measurements, and show that this model predicts Bell inequality violations for measurements on correlated spins. A discussion is give of a number of well-known quantum paradoxes, showing how these can be treated in a realistic model of measurement. Our theory resolves a number of practical and philosophical issues in quantum measurement, and we compare it with earlier theories.

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Peter D. Drummond, Margaret D. Reid. 2019-09-04. Q-functions as models of physical reality. https://doi.org/10.1103/physrevresearch.2.033266

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