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Cross-diffusion systems arise as hydrodynamic limits of lattice multi-species interacting particle models. The objective of this work is to provide a numerical scheme for the simulation of the cross-diffusion system identified in [J.…

Numerical Analysis · Mathematics 2023-09-06 Jad Dabaghi , Virginie Ehrlacher , Christoph Strössner

We study the convergence of the new family of mimetic finite difference schemes for linear diffusion problems recently proposed in [38]. In contrast to the conventional approach, the diffusion coefficient enters both the primary mimetic…

Numerical Analysis · Mathematics 2016-12-07 G. Manzini , K. Lipnikov , J. D. Moulton , M. Shashkov

We study gas mixing in a simulated Milky Way-mass galaxy's circumgalactic medium (CGM) using cosmological `zoom-in' simulations. We insert tracer dyes in the CGM with different gas flows (shearing, coherent, and static) and diverse physical…

Astrophysics of Galaxies · Physics 2025-07-01 Hilay Shah , Freeke van de Voort , Amit Seta , Christoph Federrath

Molecular Dynamics - Green's Functions Reaction Dynamics (MD-GFRD) is a multiscale simulation method for particle dynamics or particle-based reaction-diffusion dynamics that is suited for systems involving low particle densities. Particles…

Chemical Physics · Physics 2017-12-06 Luigi Sbailò , Frank Noé

The dispersion measure (DM) of fast radio bursts (FRBs) provides a unique way to probe ionised baryons in the intergalactic medium (IGM). Cosmological models with different parameters lead to different DM-redshift ($\mathrm{DM}-z$)…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 Adam J. Batten , Alan R. Duffy , Nastasha Wijers , Vivek Gupta , Chris Flynn , Joop Schaye , Emma Ryan-Weber

An approximate stochastic model for the topological dynamics of the periodic triangular Lorentz gas is constructed. The model, together with an extremum principle, is used to find a closed form approximation to the diffusion coefficient as…

Chaotic Dynamics · Physics 2015-06-04 C. Angstmann , G. P. Morriss

In the hydrodynamic regime, the evolution of a stochastic lattice gas with symmetric hopping rules is described by a diffusion equation with density-dependent diffusion coefficient encapsulating all microscopic details of the dynamics. This…

Statistical Mechanics · Physics 2018-02-23 Chikashi Arita , P L Krapivsky , Kirone Mallick

In this paper, we investigate the diffusion least mean square (DLMS) algorithm over fading channel, where in addition to channel noise and path-loss the inter-node-interference (INI) among neighboring nodes of a host node is also taken into…

Signal Processing · Electrical Eng. & Systems 2023-03-21 Mohammadjavad Mirzazadeh Moallem , Mehdi Korki

We develop an online optimisation algorithm for in situ calibration of collision models in simulations of rarefied gas flows. The online optimised collision models are able to achieve similar accuracy to Direct Molecular Simulation (DMS) at…

Fluid Dynamics · Physics 2024-11-21 Nicholas Daultry Ball , Jonathan F. MacArt , Justin Sirignano

Low-dimensional periodic arrays of scatterers with a moving point particle are ideal models for studying deterministic diffusion. For such systems the diffusion coefficient is typically an irregular function under variation of a control…

Chaotic Dynamics · Physics 2009-11-07 R. Klages , N. Korabel

Particle diffusion in rotating drums is studied via computer simulations using a full 3-D model which does not involve any arbitrary input parameters. The diffusion coefficient for single-component systems agree qualitatively with previous…

Condensed Matter · Physics 2009-10-28 G. A. Kohring

Implementing multicomponent diffusion models in reacting-flow simulations is computationally expensive due to the challenges involved in calculating diffusion coefficients. Instead, mixture-averaged diffusion treatments are typically used…

The diffusion approximation of stochastic gradient descent (SGD) in current literature is only valid on a finite time interval. In this paper, we establish the uniform-in-time diffusion approximation of SGD, by only assuming that the…

Machine Learning · Statistics 2022-07-12 Lei Li , Yuliang Wang

We present a systematic study of the self-diffusion coefficient for a fluid of particles interacting via the square-well pair potential by means of molecular dynamics simulations in the canonical (N,V,T) ensemble. The discrete nature of the…

Soft Condensed Matter · Physics 2018-11-14 Alexis Torres-Carbajal , Victor M. Trejos , Luz Adriana Nicasio-Collazo

We propose a mean field (MF) theory for a homogeneously driven granular gas of inelastic particles with Coulomb friction. The model contains three parameters, a normal restitution coefficient $r_n$, a maximum tangential restitution…

Statistical Mechanics · Physics 2009-10-31 Raffaele Cafiero , Stefan Luding

In order to understand how the chemical and isotopic compositions of dust grains in a gaseous turbulent protoplanetary disk are altered during their journey in the disk, it is important to determine their individual trajectories. We study…

Earth and Planetary Astrophysics · Physics 2015-05-28 Sebastien Charnoz , Laure Fouchet , Jérôme Aleon , Manuel Moreira

The dynamics of interacting particles in orbital magnetic fields are notoriously difficult to study, as this physics is inherently connected to electronic correlations in two-dimensional systems, for which no straightforward theoretical…

Quantum Gases · Physics 2026-03-27 Łukasz Iwanek , Marcin Mierzejewski , Adam S. Sajna

Systems of particles with long range interactions present two important processes: first, the formation of out-of-equilibrium quasi-stationary states (QSS), and the collisional relaxation towards Maxwell-Boltzmann equilibrium in a much…

Statistical Mechanics · Physics 2017-03-08 Fernanda P. C. Benetti , Bruno Marcos

Diffusion models (DMs) have been adopted across diverse fields with its remarkable abilities in capturing intricate data distributions. In this paper, we propose a Fast Diffusion Model (FDM) to significantly speed up DMs from a stochastic…

Computer Vision and Pattern Recognition · Computer Science 2023-10-05 Zike Wu , Pan Zhou , Kenji Kawaguchi , Hanwang Zhang

Diffusion models generate high-quality images but require dozens of forward passes. We introduce Distribution Matching Distillation (DMD), a procedure to transform a diffusion model into a one-step image generator with minimal impact on…

Computer Vision and Pattern Recognition · Computer Science 2024-10-08 Tianwei Yin , Michaël Gharbi , Richard Zhang , Eli Shechtman , Fredo Durand , William T. Freeman , Taesung Park