System driven out-of equilibrium by weak contacts with reservoirs

Thierry Bodineau; Bernard Derrida

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arXiv · 2605.01900

System driven out-of equilibrium by weak contacts with reservoirs

Thierry Bodineau·Bernard Derrida

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Abstract

The non-equilibrium behavior of particle systems driven by reservoirs has been extensively studied in recent years. In one dimension, various regimes have been explored depending on the coupling strength to the reservoirs. In this paper, we investigate the role of the dimension and of the geometry of the contacts with the reservoirs. For the symmetric simple exclusion process with point contact reservoirs, we show that in dimension 2, as in one dimension, three different regimes occur depending on the coupling strength. On the other hand in dimensions 3 and higher, there exists only a weak coupling regime which is very sensitive to the microscopic structure of the contacts. We then argue that for reservoirs with mesoscopic size contacts the macroscopic fluctuation theory remains in force and we propose an extension of the additivity principle for multiple mesoscopic reservoirs.

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Thierry Bodineau, Bernard Derrida. 2026-05-03. System driven out-of equilibrium by weak contacts with reservoirs. https://arxiv.org/abs/2605.01900

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