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arXiv · 2507.13593

Forward-Time Equivalent of a "Retrocausal" Diffusion Hidden Variable Model for Quantum Mechanics

William S. DeWitt·Benjamin H. Feintzeig
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Abstract

A recently proposed stochastic hidden variable model for quantum mechanics has been claimed to involve "retrocausality" due to the appearance of equations of motion with future-time boundary conditions. We formulate an equivalent system of forward-time equations of motion that gives rise to the same trajectories as solutions, but involves only initial-time boundary conditions. The forward-time dynamics involves a guidance term for the dynamical variables, determined by the phase-space distribution corresponding to a quantum wavefunction. We show, however, that this particular guidance term can be recovered as the mean-field limit of averaged pairwise interactions among an ensemble of finitely many particles.

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William S. DeWitt, Benjamin H. Feintzeig. 2025-07-18. Forward-Time Equivalent of a "Retrocausal" Diffusion Hidden Variable Model for Quantum Mechanics. https://arxiv.org/abs/2507.13593

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