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Decomposition of force fluctuations far from equilibrium

Kumiko Hayashi·Shin-ichi Sasa
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Abstract

By studying a nonequilibrium Langevin system, we find that a simple condition determines the decomposition of the coarse-grained force into a dissipative force, an effective driving force and noise. From this condition, we derive a new universal inequality, $D \ge γ\mud^2 T$, relating the diffusion constant $D$, the differential mobility $\mud$, the bare friction constant $γ$ and the temperature $T$. Due to the general nature of the argument we present, we believe that our idea concerning this decomposition can be applied to a wide class of systems far from equilibrium.

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Kumiko Hayashi, Shin-ichi Sasa. 2004-12-17. Decomposition of force fluctuations far from equilibrium. https://doi.org/10.1103/physreve.71.020102

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