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arXiv · 2505.00716

Physical origins and limitations of canonical quantum measurement behavior

Jonathan F. Schonfeld
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Abstract

I review and augment my work of the last few years on the physical origins and limitations of canonical quantum measurement behavior. Central to this work is a detailed analysis of the microstructure of real measurement devices. Particular attention is paid to the Mott problem, which addresses a simpler version of canonical quantum measurement behavior: It asks why an alpha particle emitted in a nuclear decay produces one and only one track in a cloud chamber. My analysis - entirely consistent with unitarity - leads to an emergent, approximate Born rule supported by experiment, with possible breakdown at very small probability density. I argue that a similar picture applies to other measurement scenarios, including Geiger counters, the Stern-Gerlach experiment and superconducting qubits.

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Jonathan F. Schonfeld. 2025-10-26. Physical origins and limitations of canonical quantum measurement behavior. https://arxiv.org/abs/2505.00716

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