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Related papers: The Bare Diffusion Coefficient and the Peculiar Ve…

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We consider the movement of a particle advected by a random flow of the form $\vv+\delta \bF(\vx)$, with $\vv\in\R^d$ a constant drift, $\bF(\vx)$ -- the fluctuation -- given by a zero mean, stationary random field and $\delta\ll 1$ so that…

Chaotic Dynamics · Physics 2015-06-26 Tomasz Komorowski , Lenya Ryzhik

We report new results about the anomalous diffusion of a particle in an aging medium. For each given age, the quasi-stationary particle velocity is governed by a generalized Langevin equation with a frequency-dependent friction coefficient…

Statistical Mechanics · Physics 2015-06-24 Noelle Pottier , Alain Mauger

Odd-diffusive systems are characterized by transverse responses and exhibit unconventional behaviors in interacting systems. To address the dynamical interparticle rearrangements in a minimal system, we here exactly solve the problem of two…

Statistical Mechanics · Physics 2024-07-19 Amelie Langer , Abhinav Sharma , Ralf Metzler , Erik Kalz

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

A practical correction formula relating the self-diffusion coefficient of dense liquids from molecular dynamics simulations with periodic boundary conditions to the self-diffusion coefficient in the thermodynamic limit is discussed. This…

Statistical Mechanics · Physics 2024-02-15 Sergey Khrapak

We study the velocity autocorrelation function (VACF) of a driven granular fluid in the stationary state in 3 dimensions. As the critical volume fraction of the glass transition in the corresponding elastic system is approached, we observe…

Statistical Mechanics · Physics 2011-10-05 Andrea Fiege , Timo Aspelmeier , Annette Zippelius

The one-dimensional coagulation-diffusion process describes the strongly fluctuating dynamics of particles, freely hopping between the nearest-neighbour sites of a chain such that one of them disappears with probability 1 if two particles…

Statistical Mechanics · Physics 2016-02-23 Xavier Durang , Jean-Yves Fortin , Malte Henkel

Macroscopic quantum tunneling is described using the master equation for the reduced Wigner function of an open quantum system at zero temperature. Our model consists of a particle trapped in a cubic potential interacting with an…

Quantum Physics · Physics 2011-08-04 Esteban Calzetta , Enric Verdaguer

The velocity autocorrelation function (VAF) for a two-dimensional one-component plasma (OCP) is investigated by employing molecular dynamics techniques. The VAF exhibits well defined oscillations whose frequency is independent of the…

Mesoscale and Nanoscale Physics · Physics 2016-02-15 Girija S. Dubey , Godfrey Gumbs

We perform Brownian dynamics simulations for studying the self-diffusion in two-dimensional (2D) dusty plasma liquids, in terms of both mean-square displacement and velocity autocorrelation function (VAF). Super-diffusion of charged dust…

Plasma Physics · Physics 2009-02-25 Lu-Jing Hou , Alexander Piel , P. K. Shukla

Excluded-volume effects can play an important role in determining transport properties in diffusion of particles. Here, the diffusion of finite-sized hard-core interacting particles in two or three dimensions is considered systematically…

Analysis of PDEs · Mathematics 2012-01-06 Maria Bruna , S. Jonathan Chapman

A closed set of \textit{exact} equations describing statistical theory of turbulent self-diffusion by multivariate-normal turbulent velocity field is derived. In doing so, we first suggest exact formulas for correlations…

Statistical Mechanics · Physics 2007-05-23 R. Vikram Raj Pandya

In this letter we present a measurement of the phase-space density distribution (PSDD) of ultra-cold \Rb atoms performing 1D anomalous diffusion. The PSDD is imaged using a direct tomographic method based on Raman velocity selection. It…

Atomic Physics · Physics 2017-08-16 Gadi Afek , Jonathan Coslovsky , Arnaud Courvoisier , Oz Livneh , Nir Davidson

A formalism using a double Laplace Fourier transform of the transport equation yields the return probabilities of the vacancy in the vicinity of the tracer atom in the presence of solute-vacancy interactions of arbitrary extension. Studying…

Materials Science · Physics 2016-10-11 J. L. Bocquet

Collective diffusion coefficient in a one dimensional lattice gas adsorbate is calculated using variational approach. Particles interact via either a long-range, or a long range electron-gas-mediated (for a metallic substrate), or a…

Materials Science · Physics 2009-05-26 Filip Krzyżewski , Magdalena A. Załuska-Kotur

The diffusion behavior of particles moving in complex heterogeneous environment is a very topical issue. We characterize particle's trajectory via an underdamped Langevin system driven by a Gaussian white noise with a time dependent…

Statistical Mechanics · Physics 2022-01-05 Yao Chen , Xudong Wang

In this paper we revisit the issue of the propagation of warps in thin and viscous accretion discs. In this regime warps are know to propagate diffusively, with a diffusion coefficient approximately inversely proportional to the disc…

High Energy Astrophysical Phenomena · Physics 2015-05-18 G. Lodato , D. Price

Diffusion is an ubiquitous phenomenon. It is a widespread belief that as long as the area under a current autocorrelation function converges in time, the corresponding spatiotemporal density dynamics should be diffusive. This may be viewed…

Statistical Mechanics · Physics 2025-07-04 Scott D. Linz , Jiaozi Wang , Robin Steinigeweg , Jochen Gemmer

We study velocity correlations induced by diffusion and dissipation in a simple dissipative dynamical system. We observe that diffusion, as a result of time reversible microscopic processes, leads to correlations with different spatial…

Statistical Mechanics · Physics 2009-11-07 Tong Zhou

Diffusion coefficients are essential microphysics input for modeling white dwarf evolution, as they impact phase separation at crystallization and sedimentary heat sources. Present schemes for computing diffusion coefficients are accurate…

Solar and Stellar Astrophysics · Physics 2022-04-06 M. E. Caplan , E. B. Bauer , I. F. Freeman