Comment on "Entropic Costs of Extracting Classical Ticks from a Quantum Clock"

Longyan Gong

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arXiv · 2605.21833

Comment on "Entropic Costs of Extracting Classical Ticks from a Quantum Clock"

Longyan Gong

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Abstract

A recent Letter by Wadhia et al. reports a realization of a quantum clock using a double quantum dot (DQD) [Phys. Rev. Lett. 135, 200407 (2005)]. This Comment identifies two fundamental issues: (I) the claimed ``quantum clock" exhibits only classical behavior and lacks intrinsic temporal correlations between ticks; it is not sufficient for accurate time as a good clock. (II) the thermodynamic analysis misassigns entropy production and conflates amplification with measurement; the reported combined entropy is an engineering dissipation, not a fundamental cost of quantum timekeeping.

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Longyan Gong. 2026-05-20. Comment on "Entropic Costs of Extracting Classical Ticks from a Quantum Clock". https://arxiv.org/abs/2605.21833

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