Brownian yet non-Gaussian diffusion in heterogeneous media: from superstatistics to homogenization

被引：43

作者：

Postnikov, E. B. ^{[1
,2
]}

Chechkin, A. ^{[3
,4
]}

Sokolov, I. M. ^{[5
,6
]}

机构：

[1] Kursk State Univ, Dept Theoret Phys, Radishcheva St 33, Kursk 305000, Russia

[2] Saratov State Natl Res Univ, Astrakhanskaya 83, Saratov 410012, Russia

[3] Univ Potsdam, Inst Phys & Astron, Karl Liebknecht Str 24-25, D-14476 Potsdam, Germany

[4] Akhiezer Inst Theoret Phys, Akad Skaya Str 1, UA-61108 Kharkov, Ukraine

[5] Humboldt Univ, Inst Phys, Newtonstr 15, D-12489 Berlin, Germany

[6] Humboldt Univ, IRIS Adlershof, Newtonstr 15, D-12489 Berlin, Germany

来源：

NEW JOURNAL OF PHYSICS | 2020年 / 22卷 / 06期

基金：

俄罗斯科学基金会;

关键词：

diffusing diffusivity; Brownian yet non-Gaussian diffusion; position-dependent diffusion coefficient; superstatistics; homogenization; DYNAMICAL HETEROGENEITIES; ANOMALOUS DIFFUSION;

D O I：

10.1088/1367-2630/ab90da

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We discuss the situations under which Brownian yet non-Gaussian (BnG) diffusion can be observed in the model of a particle's motion in a random landscape of diffusion coefficients slowly varying in space (quenched disorder). Our conclusion is that such behavior is extremely unlikely in the situations when the particles, introduced into the system at random att= 0, are observed from the preparation of the system on. However, it indeed may arise in the case when the diffusion (as described in Ito interpretation) is observed under equilibrated conditions. This paradigmatic situation can be translated into the model of the diffusion coefficient fluctuating in time along a trajectory, i.e. into a kind of the 'diffusing diffusivity' model.

引用

页数：17