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Drift-Diffusion in Mangled Worlds Quantum Mechanics

Robin Hanson
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Abstract

In Everett's many worlds interpretation, where quantum measurements are seen as decoherence events, inexact decoherence may let large worlds mangle the memories of observers in small worlds, creating a cutoff in observable world size. I solve a growth-drift-diffusion-absorption model of such a mangled worlds scenario, and show that it reproduces the Born probability rule closely, though not exactly. Thus deviations from exact decoherence can allow the Born rule to be derived in a many worlds approach via world counting, using a finite number of worlds and no new fundamental physics.

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Robin Hanson. 2003-03-18. Drift-Diffusion in Mangled Worlds Quantum Mechanics. https://doi.org/10.1098/rspa.2005.1640

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