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Related papers: Subordinated diffusion and CTRW asymptotics

200 papers

We consider the linear response of systems modelled by continuous-time random walks (CTRW) and by fractional Fokker-Planck equations under the influence of time-dependent external fields. We calculate the corresponding response functions…

Statistical Mechanics · Physics 2009-11-07 I. M. Sokolov , A. Blumen , J. Klafter

In this article, we generalize the recent Discrete Time Random Walk (DTRW) algorithm, which was introduced for the computation of probability densities of fractional diffusion. Although it has the same computational complexity and shares…

Computational Physics · Physics 2018-08-20 Gurtek Gill , Peter Straka

We present a numerical method for the Monte Carlo simulation of uncoupled continuous-time random walks with a Levy alpha-stable distribution of jumps in space and a Mittag-Leffler distribution of waiting times, and apply it to the…

Statistical Mechanics · Physics 2013-03-19 Daniel Fulger , Enrico Scalas , Guido Germano

We show that the generalized diffusion coefficient of a subdiffusive intermittent map is a fractal function of control parameters. A modified continuous time random walk theory yields its coarse functional form and correctly describes a…

Chaotic Dynamics · Physics 2015-06-26 N. Korabel , A. V. Chechkin , R. Klages , I. M. Sokolov , V. Yu. Gonchar

Anomalous diffusion, in particular subdiffusion, is frequently invoked as a mechanism of motion in dense biological media, and may have a significant impact on the kinetics of binding/unbinding events at the cellular level. In this work we…

Statistical Mechanics · Physics 2015-06-10 S. B. Yuste , E. Abad , K. Lindenberg

The~numerical solutions to a non-linear Fractional Fokker--Planck (FFP) equation are studied estimating the generalized diffusion coefficients. The~aim is to model anomalous diffusion using an FFP description with fractional velocity…

Plasma Physics · Physics 2018-10-08 Johan Anderson , Sara Moradi , Tariq Rafiq

The non-Markovian continuous-time random walk model, featuring fat-tailed waiting times and narrow distributed displacements with a non-zero mean, is a well studied model for anomalous diffusion. Using an analytical approach, we recently…

Statistical Mechanics · Physics 2023-09-18 Wanli Wang , Eli Barkai

We consider the radiative transport equation in which the time derivative is replaced by the Caputo derivative. Such fractional-order derivatives are related to anomalous transport and anomalous diffusion. In this paper we describe how the…

Mathematical Physics · Physics 2017-03-08 Manabu Machida

For the first time, the diffusion phase diagram in highly confined colloidal systems, predicted by Continuous Time Random Walk (CTRW), is experimentally obtained. Temporal and spatial fractional exponents, $\alpha$ and $\mu$, introduced…

Disordered Systems and Neural Networks · Physics 2015-05-27 M. Palombo , A. Gabrielli , S. De Santis , C. Cametti , G. Ruocco , S. Capuani

A Langevin equation with a special type of additive random source is considered. This random force presents a fractional order derivative of white noise, and leads to a power-law time behavior of the mean square displacement of a particle,…

chao-dyn · Physics 2009-10-31 V. Kobelev , E. Romanov

Continuous time random walks (CTRWs) are versatile models for anomalous diffusion processes that have found widespread application in the quantitative sciences. Their scaling limits are typically non-Markovian, and the computation of their…

Probability · Mathematics 2014-07-25 Mark M. Meerschaert , Peter Straka

The transport equation of active motion is generalised to consider time-fractional dynamics for describing the anomalous diffusion of self-propelled particles observed in many different systems. In the present study, we consider an…

Statistical Mechanics · Physics 2023-10-27 Francisco J. Sevilla , Guillermo Chacón-Acosta , Trifce Sandev

We consider the continuous time random walk model (CTRW) of tracer's motion in porous medium flows based on the experimentally determined distributions of pore velocity and pore size reported in Holzner et al. Phys. Rev. E 92, 013015…

Statistical Mechanics · Physics 2017-05-31 Itzhak Fouxon , Markus Holzner

Charge transport processes in disordered complex media are accompanied by anomalously slow relaxation for which usually a broad distribution of relaxation times is adopted. To account for those properties of the environment, a standard…

Statistical Mechanics · Physics 2009-11-10 Ewa Gudowska-Nowak , Kinga Bochenek , Agnieszka Jurlewicz , Karina Weron

The continuous-time random walk (CTRW) is a pure-jump stochastic process with several applications in physics, but also in insurance, finance and economics. A definition is given for a class of stochastic integrals driven by a CTRW, that…

Statistical Mechanics · Physics 2013-03-19 Guido Germano , Mauro Politi , Enrico Scalas , René L. Schilling

We consider continuous time random walks (CTRW) and discuss situations pertinent to aging. These correspond to the case when the initial state of the system is known not at preparation (at $t=0$) but at the later instant of time $t_1>0$…

Statistical Mechanics · Physics 2007-10-16 V. Yu. Zaburdaev , I. M. Sokolov

A detailed study is presented for a large class of uncoupled continuous-time random walks (CTRWs). The master equation is solved for the Mittag-Leffler survival probability. The properly scaled diffusive limit of the master equation is…

Disordered Systems and Neural Networks · Physics 2009-11-10 Enrico Scalas , Rudolf Gorenflo , Francesco Mainardi

The basic conceptual picture and theoretical basis for development of transport equations in porous media are examined. The general form of the governing equations is derived for conservative chemical transport in heterogeneous geological…

Statistical Mechanics · Physics 2015-06-24 Brian Berkowitz , Joseph Klafter , Ralf Metzler , Harvey Scher

In this work a Feynman-Kac path integral method based on Levy measure has been proposed for solving the Cauchy problems associated with the space-time fractional Schroedinger equations arising in interacting systems in fractional quantum…

Quantum Physics · Physics 2023-06-27 Sumita Datta , Radhika Prosad Datta

Anomalous transport in a tilted periodic potential is investigated numerically within the framework of the fractional Fokker-Planck dynamics via the underlying CTRW. An efficient numerical algorithm is developed which is applicable for an…

Statistical Mechanics · Physics 2009-11-11 E. Heinsalu , M. Patriarca , I. Goychuk , G. Schmid , P. Hänggi