TY  - JOUR
A1  - Chechkin, Aleksei V.
A1  - Seno, Flavio
A1  - Metzler, Ralf
A1  - Sokolov, Igor M.
T1  - Brownian yet Non-Gaussian Diffusion: From Superstatistics to Subordination of Diffusing Diffusivities
T2  - Physical review : X, Expanding access
N2  - A growing number of biological, soft, and active matter systems are observed to exhibit normal diffusive dynamics with a linear growth of the mean-squared displacement, yet with a non-Gaussian distribution of increments. Based on the Chubinsky-Slater idea of a diffusing diffusivity, we here establish and analyze a minimal model framework of diffusion processes with fluctuating diffusivity. In particular, we demonstrate the equivalence of the diffusing diffusivity process with a superstatistical approach with a distribution of diffusivities, at times shorter than the diffusivity correlation time. At longer times, a crossover to a Gaussian distribution with an effective diffusivity emerges. Specifically, we establish a subordination picture of Brownian but non-Gaussian diffusion processes, which can be used for a wide class of diffusivity fluctuation statistics. Our results are shown to be in excellent agreement with simulations and numerical evaluations.
Y1  - 2017
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/46728
SN  - 2160-3308
VL  - 7
PB  - American Physical Society
CY  - College Park
ER  -