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This study explores the integration of a diffusion control parameter into the chaotic dynamics of a modified bouncing ball model. By extending beyond simple elastic collisions, the model introduces elements that affect the diffusive…

We introduce a simple model of deterministic particles in weakly disordered media which exhibits a transition from normal to anomalous diffusion. The model consists of a set of non-interacting overdamped particles moving on a disordered…

Disordered Systems and Neural Networks · Physics 2017-04-26 M. Hidalgo-Soria , R. Salgado-García

Mode separation, namely how sharply a distribution fragments into barrier-separated clusters, is a fundamental geometric property of densities, difficult to quantify in high dimensions. It is structurally distinct from dispersion, yet…

Machine Learning · Statistics 2026-05-12 Shaul Tolkovsky , Ori Meidler , Or Zuk

We report the results of MD numerical simulations for a one component model of a plasma in the weakly coupled regime, at different values of temperature $T$ and applied magnetic field $\vec B$, in which the diffusion coefficient $D_{\perp}$…

Plasma Physics · Physics 2016-05-03 Lorenzo Valvo , Andrea Carati

The scaling form of the whole distribution P(D) of the random diffusion coefficient D(x) in a model of classically diffusing particles is investigated. The renormalization group approach above the lower critical dimension d=0 is applied to…

Condensed Matter · Physics 2009-10-22 Yan-Chr Tsai , Yonathan Shapir

In this paper we present a new model for modeling the diffusion and relative dispersion of particles in homogeneous isotropic turbulence. We use an Heisenberg-like Hamiltonian to incorporate spatial correlations between fluid particles,…

Fluid Dynamics · Physics 2012-12-18 Thomas Burgener , Dirk Kadau , Hans Jürgen Herrmann

Re-analyzing the old phase shift data of I=0, \pi\pi (I=1/2, K\pi) scattering, we show an evidence for existence of the \sigma-particle (\kappa-particle) with a comparatively light mass, which has been missing for a long time: In the…

High Energy Physics - Phenomenology · Physics 2009-10-30 Taku Ishida , Muneyuki Ishida , Shin Ishida , Kunio Takamatsu , Tsuneaki Tsuru

The tensor analyzing power $T_{20}$ and the polarization transfer coefficients $\kappa_0 (= 3/2 K_y^y)$ and $K_{xz}^y$ are investigated for dp backward elastic scattering by the invariant-amplitude method. Discrepancies between the…

Nuclear Theory · Physics 2016-09-08 M. Tanifuji , S. Ishikawa , Y. Iseri

A stochastic model is proposed for the acceleration of non-relativistic particles yielding to energy spectra with a shape of a Weibull\textquoteright s function. Such particle distribution is found as the stationary solution of a…

Space Physics · Physics 2016-02-23 G. Pallocchia , M. Laurenza , G. Consolini

Diffusion models have marked a significant breakthrough in the synthesis of semantically coherent images. However, their extensive noise estimation networks and the iterative generation process limit their wider application, particularly on…

Computer Vision and Pattern Recognition · Computer Science 2024-07-08 Yuzhe Yao , Feng Tian , Jun Chen , Haonan Lin , Guang Dai , Yong Liu , Jingdong Wang

We propose a method to extract from experimental data the subdiffusion parameter $\alpha$ and subdiffusion coefficient $D_\alpha$ which are defined by means of the relation $<x^2> =2D_\alpha/\Gamma(1+\alpha) t^\alpha$ where $<x^2>$ denotes…

Statistical Mechanics · Physics 2013-05-29 T. Kosztolowicz , K. Dworecki , St. Mrowczynski

In hydrology, the degradation coefficient is one of the key parameters to describe the water quality change and to determine the water carrying capacity. This paper is devoted to identify the degradation coefficient in an anomalous…

Analysis of PDEs · Mathematics 2018-12-04 Guang-Hui Zheng , Ming-Hui Ding

We analyze the force on a point charge moving at relativistic speeds parallel to the surface of a uniaxial dielectric. Two cases are examined: a lossless dielectric with no dispersion and a dielectric with a plasma type response. The…

Classical Physics · Physics 2013-04-19 Primož Rebernik Ribič , Rudolf Podgornik

In this work, we consider the numerical recovery of a spatially dependent diffusion coefficient in a subdiffusion model from distributed observations. The subdiffusion model involves a Caputo fractional derivative of order $\alpha\in(0,1)$…

Numerical Analysis · Mathematics 2021-01-12 Bangti Jin , Zhi Zhou

Turbulent transport near the X-point of a large tokamak is examined using local, gradient-driven simulations that determine the saturated plasma profiles. The distribution of a representative set of particle tracers evolving within these…

Plasma Physics · Physics 2026-03-06 Fabio Moretti , Francesco Cianfrani , Nakia Carlevaro , Giovanni Montani

We study in details the dynamics of the one dimensional symmetric trap model, via a real-space renormalization procedure which becomes exact in the limit of zero temperature. In this limit, the diffusion front in each sample consists in two…

Condensed Matter · Physics 2009-11-10 Cecile Monthus

Diffusion models have emerged as state-of-the-art generative models for image generation. However, sampling from diffusion models is usually time-consuming due to the inherent autoregressive nature of their sampling process. In this work,…

Machine Learning · Computer Science 2024-05-28 Zhiwei Tang , Jiasheng Tang , Hao Luo , Fan Wang , Tsung-Hui Chang

Spatial intermittency in fully developed turbulence is an established feature of astrophysical plasma fluctuations and in particular apparent in the interplanetary medium by in situ observations. In this situation the classical…

Astrophysics · Physics 2017-08-02 M. P. Leubner , Z. Voros , W. Baumjohann

We present results on tagged particle diffusion in a meso-scale lattice model for sheared amorphous material in athermal quasi-static conditions. We find a short time diffusive regime and a long time diffusive regime whose diffusion…

Soft Condensed Matter · Physics 2018-10-10 Botond Tyukodi , Craig E Maloney , Damien Vandembroucq

We expand the off-resonant scattering theory for particle diffusion in magnetized current filaments that can be typically compared to astrophysical jets, including active galactic nucleus jets. In a high plasma beta region where the…

Astrophysics · Physics 2009-11-13 Mitsuru Honda , Yasuko S. Honda