Unattainability of Carnot efficiency in thermal motors: Coarse-graining and entropy production of Feynman-Smoluchowski ratchet

Yohei Nakayama, Kyogo Kawaguchi, Naoko Nakagawa

We revisit and analyze the thermodynamic efficiency of the Feynman-Smoluchowski (FS) ratchet, a classical thought experiment describing an autonomous heat-work converter. Starting…