TY  - JOUR
A1  - Metzler, Ralf
T1  - Superstatistics and non-Gaussian diffusion
JF  - The European physical journal special topics
N2  - Brownian motion and viscoelastic anomalous diffusion in homogeneous environments are intrinsically Gaussian processes. In a growing number of systems, however, non-Gaussian displacement distributions of these processes are being reported. The physical cause of the non-Gaussianity is typically seen in different forms of disorder. These include, for instance, imperfect "ensembles" of tracer particles, the presence of local variations of the tracer mobility in heteroegenous environments, or cases in which the speed or persistence of moving nematodes or cells are distributed. From a theoretical point of view stochastic descriptions based on distributed ("superstatistical") transport coefficients as well as time-dependent generalisations based on stochastic transport parameters with built-in finite correlation time are invoked. After a brief review of the history of Brownian motion and the famed Gaussian displacement distribution, we here provide a brief introduction to the phenomenon of non-Gaussianity and the stochastic modelling in terms of superstatistical and diffusing-diffusivity approaches.
KW  - Brownian diffusion
KW  - anomalous diffusion
KW  - dynamics
KW  - kinetic-theory
KW  - models
KW  - motion
KW  - nanoparticles
KW  - nonergodicity
KW  - statistics
KW  - subdiffusion
Y1  - 2020
U6  - https://doi.org/10.1140/epjst/e2020-900210-x
SN  - 1951-6355
SN  - 1951-6401
VL  - 229
IS  - 5
SP  - 711
EP  - 728
PB  - Springer
CY  - Heidelberg
ER  -