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arXiv · 1211.6580

Diffusion in nonuniform temperature and its geometric analog

Matteo Polettini
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Abstract

We propose a Langevin equation for systems in an environment with nonuniform temperature. At odds with an older proposal, ours admits a locally Maxwellian steady state, local equipartition holds and for detailed-balanced (reversible) systems statistical and physical entropies coincide. We describe its thermodynamics, which entails a generalized version of the First Law and Clausius's characterization of reversibility. Finally, we show that a Brownian particle constrained into a smooth curve behaves according to our equation, as if experiencing nonuniform temperature.

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Matteo Polettini. 2013-03-19. Diffusion in nonuniform temperature and its geometric analog. https://doi.org/10.1103/physreve.87.032126

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