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Related papers: Generalised fractional diffusion equations for sub…

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Recently, in the paper: T. Koszto{\l}owicz and A. Dutkiewicz, Phys. Rev. E \textbf{104}, 014118 (2021) the $g$--subdiffusion equation with fractional Caputo time derivative with respect to another function $g$ has been considered. This…

Statistical Mechanics · Physics 2021-10-20 Tadeusz Kosztołowicz , Aldona Dutkiewicz

In this paper we present stochastic foundations of fractional dynamics driven by fractional material derivative of distributed order-type. Before stating our main result we present the stochastic scenario which underlies the dynamics given…

Probability · Mathematics 2015-10-02 Marcin Magdziarz , Marek Teuerle

In physics, phenomena of diffusion and wave propagation have great relevance; these physical processes are governed in the simplest cases by partial differential equations of order 1 and 2 in time, respectively. By replacing the time…

General Mathematics · Mathematics 2019-12-10 Armando Consiglio , Francesco Mainardi

In the present Short Note an idea is proposed to explain the emergence and the observation of processes in complex media that are driven by fractional non-Markovian master equations. Particle trajectories are assumed to be solely Markovian…

Statistical Mechanics · Physics 2015-06-19 Gianni Pagnini

In this work, we present and analyse a system of coupled partial differential equations, which models tumour growth under the influence of subdiffusion, mechanical effects, nutrient supply, and chemotherapy. The subdiffusion of the system…

Analysis of PDEs · Mathematics 2021-10-08 Marvin Fritz , Christina Kuttler , Mabel L. Rajendran , Barbara Wohlmuth , Laura Scarabosio

We formulate a compounded random walk that is physically well defined on both finite and infinite domains, and samples space-dependent forces throughout jumps. The governing evolution equation for the walk limits to a space-fractional…

Statistical Mechanics · Physics 2025-11-25 Christopher N. Angstmann , Daniel S. Han , Bruce I. Henry , Boris Z. Huang , Zhuang Xu

In this paper, we investigate the solutions for a generalized fractional diffusion equation that extends some known diffusion equations by taking a spatial time-dependent diffusion coefficient and an external force into account, which…

Mathematical Physics · Physics 2012-01-12 Long-jin Lv , Jian-Bin Xiao , Lin Zhang

In this note we consider generalized diffusion equations in which the diffusivity coefficient is not necessarily constant in time, but instead it solves a nonlinear fractional differential equation involving fractional Riemann-Liouville…

Probability · Mathematics 2022-09-21 Roberto Garra , Elena Issoglio , Giorgio S. Taverna

In this paper the multi-dimensional random walk models governed by distributed fractional order differential equations and multi-term fractional order differential equations are constructed. The scaling limits of these random walks to a…

Dynamical Systems · Mathematics 2007-05-23 Erik Andries , Sabir Umarov , Stanly Steinberg

The movement of organisms and cells can be governed by occasional long distance runs, according to an approximate L\'evy walk. For T cells migrating through chronically-infected brain tissue, runs are further interrupted by long pauses, and…

Biological Physics · Physics 2020-03-06 Gissell Estrada-Rodriguez , Heiko Gimperlein , Kevin J. Painter , Jakub Stocek

An intermittent nonlinear map generating subdiffusion is investigated. Computer simulations show that the generalized diffusion coefficient of this map has a fractal, discontinuous dependence on control parameters. An amended continuous…

Fractional diffusion equations are widely used to describe anomalous diffusion processes where the characteristic displacement scales as a power of time. For processes lacking such scaling the corresponding description may be given by…

Statistical Mechanics · Physics 2007-05-23 I. M. Sokolov , A. V. Chechkin , J. Klafter

We formulate the generalized master equation for a class of continuous time random walks in the presence of a prescribed deterministic evolution between successive transitions. This formulation is exemplified by means of an…

Statistical Mechanics · Physics 2009-11-13 S. Eule , R. Friedrich , F. Jenko , I. M. Sokolov

Mathematical models of motility are often based on random-walk descriptions of discrete individuals that can move according to certain rules. It is usually the case that large masses concentrated in small regions of space have a great…

Physics and Society · Physics 2022-11-23 Carles Falcó

In this paper we study $g$-fractional diffusion on bounded domains in $\mathbb{R}^d$ with absorbing boundary conditions. We show the explicit representation of the solution and then we study the first passage time distribution, showing the…

Analysis of PDEs · Mathematics 2023-03-09 L. Angelani , R. Garra

Continuous-time random walks are generalisations of random walks frequently used to account for the consistent observations that many molecules in living cells undergo anomalous diffusion, i.e. subdiffusion. Here, we describe the…

Analysis of PDEs · Mathematics 2015-03-31 Hugues Berry , Thomas Lepoutre , Álvaro Mateos González

Levy walks define a fundamental concept in random walk theory which allows one to model diffusive spreading that is faster than Brownian motion. They have many applications across different disciplines. However, so far the derivation of a…

Statistical Mechanics · Physics 2016-07-08 J. P. Taylor-King , R. Klages , S. Fedotov , R. A. Van Gorder

Reaction-diffusion equations are one of the most common mathematical models in the natural sciences and are used to model systems that combine reactions with diffusive motion. However, rather than normal diffusion, anomalous subdiffusion is…

Statistical Mechanics · Physics 2021-04-23 Amanda M Alexander , Sean D Lawley

The standard diffusive spreading, characterized by a Gaussian distribution with mean square displacement that grows linearly with time, can break down, for instance, under the presence of correlations and heterogeneity. In this work, we…

Statistical Mechanics · Physics 2021-10-27 M. A. F. dos Santos , E. H. Colombo , C. Anteneodo

We show an application of a subdiffusion equation with Caputo fractional time derivative with respect to another function $g$ to describe subdiffusion in a medium having a structure evolving over time. In this case a continuous transition…

Statistical Mechanics · Physics 2021-07-21 Tadeusz Kosztołowicz , Aldona Dutkiewicz