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arXiv · 2606.20278

Proposal of quantum arrival-time measurement with a Bose-Einstein condensate

Pascal Naidon·Lucas Happ·Denis Boiron
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Abstract

This work shows how a Bose-Einstein condensate of ultracold atoms could be used to address a long-standing question in quantum theory: how much time does it take for a particle to reach a detector? To this end, we propose a realistic experimental setup, whose key idea is not to measure arrival times directly, but the arrival flux on the detector as a function of its position. This novel approach not only solves practical issues with having a detector close to the system, but also results in signals that allow to unambiguously distinguish different theoretical predictions. This proposal raises prospects for resolving the decades-old debate on this fundamental issue.

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Pascal Naidon, Lucas Happ, Denis Boiron. 2026-06-18. Proposal of quantum arrival-time measurement with a Bose-Einstein condensate. https://arxiv.org/abs/2606.20278

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