Jim Lutsko

Jim Lutsko

My interests include Statistical Physics; Crystallization; Density Functional Theory, Simulation methods - particularly rare event techniques, Protein physics, Granular physics and Crystal Growth. I am based in the Physics of Complex Systems and Statistical Mechanics group at the Universite Libre de Bruxelles.

[053] Non-extensive diffusion as nonlinear response

J. F. Lutsko and J. P. Boon, "Non-extensive diffusion as nonlinear response", EuroPhys. Lett., 71, 906 (2005) http://jimlutsko.github.io/files/Lutsko_EPL_2005.pdf

Abstract

The porous-media equation has been proposed as a phenomenological ”non-extensive” generalization of classical diffusion. Here, we show that a very similar equation can be derived, in a systematic manner, for a classical fluid by assuming nonlinear response, i.e. that the diffusive flux depends on gradients of a power of the concentration. The present equation distinguishes from the porous-media equation in that it describes generalized classical diffusion, i.e. with r/sqrt(Dt scaling, but with a generalized Einstein relation, and with power-law probability distributions typical of non-extensive statistical mechanics.)