Proximity-measurement induced random localization in quantum fluids

Pushkar Mohile; Paul M. Goldbart

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arXiv · 2507.23085

Proximity-measurement induced random localization in quantum fluids

Pushkar Mohile·Paul M. Goldbart

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Abstract

Proximity measurements probe whether pairs of particles are close to one another. We consider the impact of post-selected random proximity measurements on a quantum fluid of many distinguishable particles. We show that such measurements induce random spatial localization of a fraction of the particles, and yet preserve homogeneity macroscopically. Eventually, all particles localize, with a distribution of localization lengths that saturates at a scale controlled by the typical measurement rate. The steady-state distribution of these lengths is governed by a familiar scaling form.

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Pushkar Mohile, Paul M. Goldbart. 2025-07-30. Proximity-measurement induced random localization in quantum fluids. https://arxiv.org/abs/2507.23085

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