Characterising the precision of a clock without any external time reference

Pablo Á. Domínguez; Christopher Chubb; Mischa P. Woods

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arXiv · 2609.31832

Characterising the precision of a clock without any external time reference

Pablo Á. Domínguez·Christopher Chubb·Mischa P. Woods

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Abstract

Determining a clock's precision usually requires comparison with a better time reference, yet no ideal reference is physically attainable. We show how a single clock can characterise its own precision using only a signal splitter and delayed trigger, whose uncertainty is explicitly accounted for. The resulting estimator depends only on tick-count statistics. A purpose-built electronic circuit validates the method without an external timekeeper or a second clock.

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Pablo Á. Domínguez, Christopher Chubb, Mischa P. Woods. 2026-09-25. Characterising the precision of a clock without any external time reference. https://arxiv.org/abs/2609.31832

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