Non-anomalous diffusion is not always Gaussian

作者：Forte Giuseppe^*; Cecconi Fabio; Vulpiani Angelo

来源：European Physical Journal B, 2014, 87(5): 102.

DOI：10.1140/epjb/e2014-40956-0

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.

• 出版日期2014-5-1