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Related papers: On Fractional Diffusion and its Relation with Cont…

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When the memory parameter of the elephant random walk is above a critical threshold, the process becomes superdiffusive and, once suitably normalised, converges to a non-Gaussian random variable. In a recent paper by the three first…

Probability · Mathematics 2024-09-12 Hélène Guérin , Lucile Laulin , Kilian Raschel , Thomas Simon

In this paper we present a study of anomalous diffusion using a Fokker-Planck description with fractional velocity derivatives. The distribution functions are found using numerical means for varying degree of fractionality observing the…

Plasma Physics · Physics 2014-12-18 Johan Anderson , Eun-jin Kim , Sara Moradi

Fractional moments have been investigated by many authors to represent the density of univariate and bivariate random variables in different contexts. Fractional moments are indeed important when the density of the random variable has…

Statistical Mechanics · Physics 2009-11-18 Giulio Cottone , Mario Di Paola , Ralf Metzler

We examine the existence of nonlinear modes and their temporal dynamics, in arrays of split-ring resonators, using a fractional extension of the Laplacian in the evolution equation. We find a closed-form expression for the dispersion…

Pattern Formation and Solitons · Physics 2020-12-30 Mario I. Molina

This paper is concerned with the fractionalized diffusion equations governing the law of the fractional Brownian motion $B_H(t)$. We obtain solutions of these equations which are probability laws extending that of $B_H(t)$. Our analysis is…

Probability · Mathematics 2015-09-28 Roberto Garra , Enzo Orsingher , Federico Polito

This paper presents a novel method for analytical derivations of marginal densities using the fractional derivatives of moment-generating functions. Although the method requires likelihood functions to take specific forms, its assumptions…

Methodology · Statistics 2026-04-06 Si-Yang Li , David A. van Dyk , Maximilian Autenrieth

This paper is a collection of recent results on discrete-time and continuous-time branching random walks. Some results are new and others are known. Many aspects of this theory are considered: local, global and strong local survival, the…

Probability · Mathematics 2018-05-07 Daniela Bertacchi , Fabio Zucca

The motion of self-propelled particles is modeled as a persistent random walk. An analytical framework is developed that allows the derivation of exact expressions for the time evolution of arbitrary moments of the persistent walk's…

Soft Condensed Matter · Physics 2015-07-28 Zeinab Sadjadi , M. Reza Shaebani , Heiko Rieger , Ludger Santen

A fractional reaction-diffusion equation is derived from a continuous time random walk model when the transport is dispersive. The exit from the encounter distance, which is described by the algebraic waiting time distribution of jump…

Statistical Mechanics · Physics 2009-11-10 Kazuhiko Seki , Mariusz Wojcik , M. Tachiya

The time variation of entropy, as an alternative to the variance, is proposed as a measure of the diffusion rate. It is shown that for linear and time-translationally invariant systems having a large-time limit for the density, at large…

Statistical Mechanics · Physics 2013-05-24 Amir Aghamohammadi , Amir H. Fatollahi , Mohammad Khorrami , Ahmad Shariati

The anomalous (i.e. non-Gaussian) dynamics of particles subject to a deterministic acceleration and a series of 'random kicks' is studied. Based on an extension of the concept of continuous time random walks to position-velocity space, a…

Statistical Mechanics · Physics 2009-11-11 R. Friedrich , F. Jenko , A. Baule , S. Eule

We consider random variables observed at arrival times of a renewal process, which possibly depends on those observations and has regularly varying steps with infinite mean. Due to the dependence and heavy tailed steps, the limiting…

Probability · Mathematics 2016-08-08 Bojan Basrak , Drago Špoljarić

In this paper we study finite velocity planar random motions with an infinite number of possible directions, where the number of changes of direction is randomized by means of an inhomogeneous fractional Poisson distribution. We first…

Probability · Mathematics 2014-11-25 R. Garra , E. Orsingher

Random flights (also called run-and-tumble walks or transport processes) represent finite velocity random motions changing direction at any Poissonian time. These models in d-dimension, can be studied giving a general formulation of the…

Statistical Mechanics · Physics 2024-10-16 Luca Angelani , Alessandro De Gregorio , Roberto Garra , Francesco Iafrate

A space fractional diffusion-like equation is introduced, which embodies the nonlocality in time, represented by the memory kernel and the non-locality in space. A specific example of the nonlocal term is considered in combination with…

Statistical Mechanics · Physics 2026-01-06 Pece Trajanovski , Irina Petreska , Katarzyna Gorska , Ljupco Kocarev , Trifce Sandev

Aging is a prevalent phenomenon in physics, chemistry and many other fields. In this paper we consider the aging process of uncoupled Continuous Time Random Walk Limits (CTRWL) which are Levy processes time changed by the inverse stable…

Probability · Mathematics 2015-10-06 Ofer Busani

Fractional extensions of the cable equation have been proposed in the literature to describe transmembrane potential in spiny dendrites. The anomalous behavior has been related in the literature to the geometrical properties of the system,…

Neurons and Cognition · Quantitative Biology 2018-08-22 Silvia Vitali , Francesco Mainardi , Gastone Castellani

The uncoupled Continuous Time Random Walk (CTRW) in one space-dimension and under power law regime is splitted into three distinct random walks: (rw_1), a random walk along the line of natural time, happening in operational time; (rw_2), a…

Probability · Mathematics 2011-04-21 Rudolf Gorenflo , Francesco Mainardi

We demonstrate that continuous time random walks in which successive waiting times are correlated by Gaussian statistics lead to anomalous diffusion with mean squared displacement <r^2(t)>~t^{2/3}. Long-ranged correlations of the waiting…

Statistical Mechanics · Physics 2015-05-14 Vincent Tejedor , Ralf Metzler

We study the average shape of fluctuations for subdiffusive processes, i.e., processes with uncorrelated increments but where the waiting time distribution has a broad power-law tail. This shape is obtained analytically by means of a…

Statistical Mechanics · Physics 2007-05-23 Santos B. Yuste , L. Acedo