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arXiv · 1806.00491

Quantum clocks are more precise than classical ones

Mischa P. Woods·Ralph Silva·Gilles Pütz·Sandra Stupar·Renato Renner
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Abstract

A clock is, from an information-theoretic perspective, a system that emits information about time. One may therefore ask whether the theory of information imposes any constraints on the maximum precision of clocks. Here we show a quantum-over-classical advantage for clocks or, more precisely, the task of generating information about what time it is. The argument is based on information-theoretic considerations: we analyse how the precision of a clock scales with its size, measured in terms of the number of bits that could be stored in it. We find that a quantum clock can achieve a quadratically improved precision compared to a purely classical one of the same size.

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Mischa P. Woods, Ralph Silva, Gilles Pütz, Sandra Stupar, Renato Renner. 2018-06-01. Quantum clocks are more precise than classical ones. https://doi.org/10.1103/prxquantum.3.010319

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