Non-anomalous diffusion is not always Gaussian

被引：15

作者：

Forte, Giuseppe ^{[1
]}

Cecconi, Fabio ^{[2
]}

Vulpiani, Angelo ^{[1
,2
]}

机构：

[1] Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy

[2] UOS Sapienza, CNR, ISC, I-00185 Rome, Italy

来源：

EUROPEAN PHYSICAL JOURNAL B | 2014年 / 87卷 / 05期

关键词：

RANDOM-WALKS; MOTION; MODELS; DYNAMICS;

D O I：

10.1140/epjb/e2014-40956-0

中图分类号：

O469 [凝聚态物理学];

学科分类号：

070205 ;

摘要：

Through the analysis of unbiased random walks on fractal trees and continuous time random walks, we show that even if a process is characterized by a mean square displacement (MSD) growing linearly with time (standard behaviour) its diffusion properties can be not trivial. In particular, we show that the following scenarios are consistent with a linear increase of MSD with time: (i) the high-order moments, <x(t)(q)> for q > 2 and the probability density of the process exhibit multiscaling; (ii) the random walk on certain fractal graphs, with non integer spectral dimension, can display a fully standard diffusion; (iii) positive order moments satisfying standard scaling does not imply an exact scaling property of the probability density.

引用

页数：9