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arXiv · 2607.13267

Quantum Motion from Local Transition Susceptibility

Jan Klaers
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Abstract

We characterize quantum motion through the susceptibility of a quantum state to weak localized state conversion. The susceptibility can be related to a passage speed characterizing local motion independently of probability transport. For individual WKB branches, it reproduces the magnitude of the local dispersion velocity in both propagating and evanescent regions. In the relativistic theory, the inferred passage speed is bounded by the speed of light, reaching this bound at the finite energy corresponding to the center of the mass gap, where the evanescent decay length equals the reduced Compton wavelength. This identifies the reduced Compton wavelength as the shortest stationary

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Jan Klaers. 2026-07-14. Quantum Motion from Local Transition Susceptibility. https://arxiv.org/abs/2607.13267

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