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Related papers: On homogenization of space-time dependent and dege…

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The present paper concerns a space-time homogenization problem for nonlinear diffusion equations with periodically oscillating (in space and time) coefficients. Main results consist of corrector results (i.e., strong convergences of…

Analysis of PDEs · Mathematics 2022-10-26 Tomoyuki Oka

We study the dynamics of flow-networks in porous media using a pore-network model. First, we consider a class of erosion dynamics assuming a constitutive law depending on flow rate, local velocities, or shear stress at the walls. We show…

Fluid Dynamics · Physics 2022-06-22 Ahmad Zareei , Deng Pan , Ariel Amir

In this paper, we study a linear convection-diffusion equation with time-dependent coefficients on a bounded interval. The problem includes inhomogeneous Dirichlet boundary conditions and is motivated by physical models where the…

Analysis of PDEs · Mathematics 2025-10-22 Konstantinos Kalimeris , Türker Özsarı

We study the action of time dependent canonical and coordinate transformations in phase space quantum mechanics. We extend the covariant formulation of the theory by providing a formalism that is fully invariant under both standard and time…

High Energy Physics - Theory · Physics 2014-11-18 Nuno Costa Dias , Joao Nuno Prata

In this paper, we numerically address the inverse problem of identifying a time-dependent coefficient in the time-fractional diffusion equation. An a priori estimate is established to ensure uniqueness and stability of the solution. A fully…

Numerical Analysis · Mathematics 2026-01-27 Arshyn Altybay

Diffusion in inhomogeneous materials can be described by both the Fick and Fokker--Planck diffusion equations. Here, we study a mixed Fick and Fokker-Planck diffusion problem with coefficients rapidly oscillating both in space and time. We…

Analysis of PDEs · Mathematics 2020-03-17 Micol Amar , Daniele Andreucci , Emilio N. M. Cirillo

This paper improves a previously established test involving only coefficients to decide a priori whether or not non-trivial symmetries of a large class of space-time dependent diffusion processes on the real line exist. When the existence…

Mathematical Physics · Physics 2024-04-19 F. Güngör

We study the homogenization of a steady diffusion equation in a highly heterogeneous medium made of two subregions separated by a periodic barrier through which the flow is proportional to the jump of the temperature by a layer conductance…

Analysis of PDEs · Mathematics 2008-11-08 Abdelhamid Ainouz

Consider a particle diffusing in a confined volume which is divided into two equal regions. In one region the diffusion coefficient is twice the value of the diffusion coefficient in the other region. Will the particle spend equal…

Dynamical Systems · Mathematics 2015-06-04 P. F. Tupper , Xin Yang

In this paper the author studies the problem of the homogenization of a diffusion perturbed by a periodic reflection invariant vector field. The vector field is assumed to have fixed direction but varying amplitude. The existence of a…

Analysis of PDEs · Mathematics 2007-05-23 Joseph G. Conlon

We prove an invariance principle for continuous-time random walks in a dynamically averaging environment on $\mathbb Z$. In the beginning, the conductances may fluctuate substantially, but we assume that as time proceeds, the fluctuations…

Probability · Mathematics 2020-09-24 Stein Andreas Bethuelsen , Christian Hirsch , Christian Mönch

The spatial diffusion of an inhomogeneous vortex tangle is studied numerically with the vortex filament model. A localized initial tangle is prepared by applying a counterflow, and the tangle is allowed to diffuse freely after the…

Soft Condensed Matter · Physics 2009-11-07 Makoto Tsubota , Tsunehiko Araki , W. F. Vinen

We study pattern-forming instabilities in reaction-advection-diffusion systems. We develop an approach based on Lyapunov-Bloch exponents to figure out the impact of a spatially periodic mixing flow on the stability of a spatially…

Pattern Formation and Solitons · Physics 2010-11-15 A. V. Straube , A. Pikovsky

We study the homogenization problem for a system of stochastic differential equation with local time terms that models a multivariate diffusion in presence of semipermeable hyperplane interfaces with oblique penetration. We show that this…

Probability · Mathematics 2024-02-05 Olga Aryasova , Ilya Pavlyukevich , Andrey Pilipenko

We consider a diffusion on a bounded domain, assuming that the system is irreducible inside the domain and that the diffusion has varying degree of degeneracy on the domain's boundary. The long-term statistical properties of typical…

Probability · Mathematics 2025-08-29 Yuri Bakhtin , Renaud Raquépas , Lai-Sang Young

We consider the homogenization for time-fractional diffusion equations in a periodic structure and we derive the homogenized time-fractional diffusion equation. Then we discuss the determination of the constant diffusion coefficient by…

Analysis of PDEs · Mathematics 2023-03-06 Atsushi Kawamoto , Manabu Machida , Masahiro Yamamoto

The time dependency of the diffusion coefficient of particles in porous media is an efficient probe of their geometry. The analysis of this quantity, measured e.g. by nuclear magnetic resonance (PGSE-NMR), can provide rich information…

Soft Condensed Matter · Physics 2013-02-13 Maximilien Levesque , Olivier Bénichou , Benjamin Rotenberg

We consider a diffusion process with coefficients that are periodic outside of an 'interface region' of finite thickness. The question investigated in the articles [1,2] is the limiting long time / large scale behaviour of such a process…

Probability · Mathematics 2009-10-05 Martin Hairer , Charles Manson

In the present work, we explore homogenization techniques for a class of switching diffusion processes whose drift and diffusion coefficients, and jump intensities are smooth, spatially periodic functions; we assume full coupling between…

Probability · Mathematics 2025-07-01 Chetan D. Pahlajani

Motivated by the task of computing normalizing constants and importance sampling in high dimensions, we study the dimension dependence of fluctuations for additive functionals of time-inhomogeneous Langevin-type diffusions on…

Statistics Theory · Mathematics 2018-09-07 Christophe Andrieu , James Ridgway , Nick Whiteley