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Related papers: Diffusion Phenomena in a Mixed Phase Space

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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

A gas of noninteracting particles diffuses in a lattice of pulsating scatterers. In the finite horizon case with bounded distance between collisions and strongly chaotic dynamics, the velocity growth (Fermi acceleration) is well described…

Chaotic Dynamics · Physics 2017-06-29 Carl P. Dettmann , Edson D. Leonel

We study a quantum particle propagating through a ``quantum mechanically chaotic'' background, described by parametric random matrices with only short range spatial correlations. The particle is found to exhibit turbulent-like diffusion…

chao-dyn · Physics 2009-10-30 Dimitri Kusnezov , Aurel Bulgac , Gui Do Dang

Behavior of the mixture of particles and dimers moving with different jump rates at reconstructed surfaces is described. Collective diffusion coefficient is calculated by the variational approach. Anisotropy of the collective particle…

Statistical Mechanics · Physics 2014-05-12 Marcin Mińkowski , Magdalena A. Załuska Kotur

Chaotic deterministic dynamics of a particle can give rise to diffusive Brownian motion. In this paper, we compute analytically the diffusion coefficient for a particular two-dimensional stochastic layer induced by the kicked Harper map.…

chao-dyn · Physics 2008-02-03 P. Leboeuf

We consider a Markovian jumping process which is defined in terms of the jump-size distribution and the waiting-time distribution with a position-dependent frequency, in the diffusion limit. We assume the power-law form for the frequency.…

Statistical Mechanics · Physics 2015-07-20 T. Srokowski , A. Kaminska

Stochastic models of diffusion with excluded-volume effects are used to model many biological and physical systems at a discrete level. The average properties of the population may be described by a continuum model based on partial…

Chemical Physics · Physics 2012-12-20 Maria Bruna , S. Jonathan Chapman

Motivated by contemporary and rich applications of anomalous diffusion processes we propose a new statistical test for fractional Brownian motion, which is one of the most popular models for anomalous diffusion systems. The test is based on…

Data Analysis, Statistics and Probability · Physics 2018-10-17 Grzegorz Sikora

Based on the non-Markov diffusion equation taking into account the spatial fractality and modeling for the generalized coefficient of particle diffusion…

Statistical Mechanics · Physics 2024-06-19 P. Kostrobij , M. Tokarchuk , B. Markovych , I. Ryzha

Shear flows, ubiquitous in space and astrophysical plasmas, can accelerate particles through turbulence excited by the Kelvin-Helmholtz instability. We present the first numerical study of particle acceleration in non-relativistic,…

High Energy Astrophysical Phenomena · Physics 2025-12-16 Mingxuan Liu , Mateusz Ruszkowski , Ellen Zweibel , Xiaochen Sun , Damiano Caprioli , Naixin Liang , Siang Peng Oh , Anatoly Spitkovsky

We present a model of anomalous diffusion consisting of an ensemble of particles undergoing homogeneous Brownian motion except for confinement by randomly placed reflecting boundaries. For power-law distributed compartment sizes, we…

Soft Condensed Matter · Physics 2015-06-09 Gerald John Lapeyre

With neutron star applications in mind, we developed a theory of diffusion in mixtures of superfluid, strongly interacting Fermi liquids. By employing the Landau theory of Fermi liquids, we determined matrices that relate the currents of…

High Energy Astrophysical Phenomena · Physics 2024-01-03 Oleg A. Goglichidze , Mikhail E. Gusakov

We develop two-dimensional Brownian dynamics simulations to examine the motion of disks under thermal fluctuations and Hookean forces. Our simulations are designed to be experimental-like, since the experimental conditions define the…

Soft Condensed Matter · Physics 2017-05-26 Manuel Pancorbo , Miguel A. Rubio , P. Domínguez-García

The dynamics of individual colloidal particles in random potential energy landscapes were investigated experimentally and by Monte Carlo simulations. The value of the potential at each point in the two-dimensional energy landscape follows a…

A diffusion process for charge distributions in a phase space is examined. The corresponding charge moves in a force field and under an action of a random field. There are the diffusion motions for coordinates and for momenta. In our model,…

Mathematical Physics · Physics 2008-03-19 E. M. Beniaminov

When very small particles are suspended in a fluid in motion, they tend to follow the flow. How such tracer particles are mixed, transported, and dispersed by turbulent flow has been successfully described by statistical models. Heavy…

Fluid Dynamics · Physics 2023-12-21 J. Bec , K. Gustavsson , B. Mehlig

When particles/molecules diffuse in systems that contain obstacles, the steady-state regime (during which the mean-square displacement scales linearly with time, $\left< r^2 \right> \sim t$) is preceded by a transient regime. It is common…

Biological Physics · Physics 2021-08-12 Nicholas Ilow , Gary W. Slater

One key issue in the probability density function (PDF) approach for disperse two-phase turbulent flows is to close the diffusion term in the phase space. This study aimed to derive a kinetic equation for particle dispersion in turbulent…

Statistical Mechanics · Physics 2020-07-15 De-yu Zhong , Guang-qian Wang , Tie-jian Li , Ming-xi Zhang , You Xia

We consider the acceleration of energetic particles by Fermi processes (i.e., diffusive shock acceleration, second order Fermi acceleration, and gradual shear acceleration) in relativistic astrophysical jets, with particular attention given…

Astrophysics · Physics 2008-11-26 Frank M. Rieger , Valenti Bosch-Ramon , Peter Duffy

For the concrete model of Brownian particles dynamics in non-uniform environment, the time interval estimation is constructed, on which phenomenological Fick laws for diffusion phenomenon description can be used. The knowledge of these…

Probability · Mathematics 2012-12-11 V. A Doobko