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arXiv · 1903.02053

Equivalence between quantum backflow and classically forbidden probability flow in a diffraction-in-time problem

Arseni Goussev
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Abstract

Quantum backflow is an interference effect in which a matter-wave packet comprised of only plane waves with non-negative momenta exhibits negative probability flux. Here we show that this effect is mathematically equivalent to the appearance of classically-forbidden probability flux when a matter-wave packet, initially confined to a semi-infinite line, expands in free space.

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Arseni Goussev. 2019-03-05. Equivalence between quantum backflow and classically forbidden probability flow in a diffraction-in-time problem. https://doi.org/10.1103/physreva.99.043626

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