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arXiv · 2609.27561

Characterizing the Carnot cycle at absolute zero: a reply to "Comment on `Proof of the Nernst theorem' "

José-María Martín-Olalla
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Abstract

This reply addresses a recent comment concerning the proof of the Nernst theorem. I clarify how a Carnot engine can consistently operate at $T=0$ through a continuous deformation of a cycle operating at $T>0$. By examining the limit where heat exchange with the cold reservoir vanishes, I show that the Nernst theorem ensures that the concept of temperature remains physically consistent at the absolute zero limit.

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José-María Martín-Olalla. 2026-09-23. Characterizing the Carnot cycle at absolute zero: a reply to "Comment on `Proof of the Nernst theorem' ". https://doi.org/10.1140/epjp%2Fs13360-026-08111-8

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