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Related papers: Diffusion in multiscale spacetimes

200 papers

In this work, the recently introduced fluid-like treatment of the phase-space has been further extended and some interesting outcomes have been presented. A modified form of the Vlasov equation has been presented which describes the…

Plasma Physics · Physics 2024-10-31 Allen Lobo , Vinod Kumar Sayal

The temporal Fokker-Planck equation is analytically integrated in an arbitrary number of spatial dimensions but with the 2D and 3D results highlighted. It is shown that a temporal power-law ansatz for the anisotropic diffusion coefficients…

Classical Physics · Physics 2013-06-27 Billy D. Jones

The problem of quantum harmonic oscillator with "regular+random" square frequency, subjected to "regular+random external force, is considered in framework of representation of the wave function by complex-valued random process. Average…

Quantum Physics · Physics 2007-05-23 A. S. Gevorkyan , A. A. Udalov

In this paper we present multivariate space-time fractional Poisson processes by considering common random time-changes of a (finite-dimensional) vector of independent classical (non-fractional) Poisson processes. In some cases we also…

Probability · Mathematics 2015-07-22 Luisa Beghin , Claudio Macci

Collisionless suspensions of inertial particles (finite-size impurities) are studied in 2D and 3D spatially smooth flows. Tools borrowed from the study of random dynamical systems are used to identify and to characterise in full generality…

Chaotic Dynamics · Physics 2007-05-23 Jeremie Bec

One obtains a probabilistic representation for the entropic generalized solutions to a nonlinear Fokker-Planck equation in $\mathbb R^d$ with multivalued nonlinear diffusion term as density probabilities of solutions to a nonlinear…

Probability · Mathematics 2018-02-01 Viorel Barbu , Michael Röckner

Probability is an important question in the ontological interpretation of quantum mechanics. It has been discussed in some trajectory interpretations such as Bohmian mechanics and stochastic mechanics. New questions arise when the…

Quantum Physics · Physics 2021-03-10 Ciann-Dong Yang , Shiang-Yi Han

The non-Markovian continuous-time random walk model, featuring fat-tailed waiting times and narrow distributed displacements with a non-zero mean, is a well studied model for anomalous diffusion. Using an analytical approach, we recently…

Statistical Mechanics · Physics 2023-09-18 Wanli Wang , Eli Barkai

Calculus and geometry are ubiquitous in the theoretical modelling of scientific phenomena, but have historically been very challenging to apply directly to real data as statistics. Diffusion geometry is a new theory that reformulates…

Differential Geometry · Mathematics 2026-02-09 Iolo Jones , David Lanners

The diffusion in two dimensions of non-interacting active particles that follow an arbitrary motility pattern is considered for analysis. Accordingly, the transport equation is generalized to take into account an arbitrary distribution of…

Statistical Mechanics · Physics 2020-09-01 Francisco J. Sevilla

We consider a stochastic differential equation for a charged particle in a stochastic magnetic field, known as A-Langevin equation. The solution of the equation is found, and the Lagrange velocity correlation function is calculated in…

Chaotic Dynamics · Physics 2007-05-23 D. Lesnik , S. Gordienko , M. Neuer , K. -H. Spatschek

The phenomenon of wave packet diffraction in space and time is described. It consists in a diffraction pattern whose spatial location progresses with time. The pattern is produced by wave packet quantum scattering off an attractive or…

Quantum Physics · Physics 2008-11-26 G. Kälbermann

The two--dimensional diffusive dynamics of test particles in a random electromagnetic field is studied. The synthetic electromagnetic fluctuations are generated through randomly placed magnetised ``clouds'' oscillating with a frequency…

Statistical Mechanics · Physics 2007-06-01 Silvia Perri , Fabio Lepreti , Vincenzo Carbone , Angelo Vulpiani

We prove that any given function can be smoothly approximated by functions lying in the kernel of a linear operator involving at least one fractional component. The setting in which we work is very general, since it takes into account…

Analysis of PDEs · Mathematics 2018-10-22 Alessandro Carbotti , Serena Dipierro , Enrico Valdinoci

In this paper diffusion processes with changing modes are studied involving the variable order partial differential equations. We prove the existence and uniqueness theorem of a solution of the Cauchy problem for fractional variable order…

Mathematical Physics · Physics 2009-03-17 Sabir Umarov , Stanly Steinberg

We study the diffusion equation with an appropriate change of variables. This equation is in general a partial differential equation (PDE). With the self-similar and related Ansat\"atze we transform the PDE of diffusion to an ordinary…

Classical Physics · Physics 2023-04-14 Imre Ferenc Barna , László Mátyás

Two models of anomalous diffusion of cosmic ray in the leaky-box approximation are compared: one of them is based on the decoupled time-space L\'evy flights and the other on fractional walks with a finite free motion velocity. Distributions…

Astrophysics of Galaxies · Physics 2020-04-03 V. V. Uchaikin , R. T. Sibatov , V. V. Saenko

A quantum theory of the universe consists of a theory of its quantum dynamics and a theory of its quantum state The theory predicts quantum multiverses in the form of decoherent sets of alternative histories describing the evolution of the…

General Relativity and Quantum Cosmology · Physics 2018-01-29 James B. Hartle

Deterministic diffusion in temporally oscillating convection is studied for particles with finite mass. The particles are assumed to obey a simple dissipative dynamical system and the particle diffusion is induced by the strange attractor.…

Chaotic Dynamics · Physics 2009-11-07 Hidetsugu Sakaguchi

It is well-known that compositions of Markov processes with inverse subordinators are governed by integro-differential equations of generalized fractional type. This kind of processes are of wide interest in statistical physics as they are…

Probability · Mathematics 2020-05-13 Luisa Beghin , Claudio Macci , Costantino Ricciuti