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arXiv · 2606.12755

Certifying Nonclassical Proper-Time Histories with a Quantum Clock

Shuai Zeng
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Abstract

Quantum clocks can acquire relativistic phases from motional or gravitational proper-time differences, but reduced clock dephasing alone does not certify nonclassical proper-time histories. We formulate this distinction as a channel-certification problem. First, we show that any two-level single-time dephasing signal, including one generated by an effective quantum proper-time label, admits a classical random proper-time representation. We then define the convex set of classical mixtures of experimentally specified proper-time histories and prove a Choi-rank separation criterion for conditioned coherent history recombination. A two-branch Ramsey protocol gives explicit bright- and dark-port population witnesses outside this classical set. The certification is operational and relative to the specified history set: it rules out classical mixtures of the same implemented proper-time histories, not arbitrary classical protocols with different histories or controls.

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Shuai Zeng. 2026-06-10. Certifying Nonclassical Proper-Time Histories with a Quantum Clock. https://arxiv.org/abs/2606.12755

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