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In this paper the theory and simulation results are presented for 3D vector cylindrical rotationally symmetric electromagnetic wave propagation in an isotropic nonlinear medium using a modified finite-difference time-domain general vector…

Pattern Formation and Solitons · Physics 2025-09-10 Caleb J. Grimms , Robert D. Nevels

We present a comprehensive model of the global properties of Alfven waves in the solar atmosphere and fast solar wind. Linear non-WKB wave transport equations are solved from the photosphere to 4 AU, and for wave periods ranging from 3…

Astrophysics · Physics 2009-11-10 S. R. Cranmer , A. A. van Ballegooijen

Astrophysical turbulence is magnetohydrodynamic (MHD) in its nature. We discuss fundamental properties of MHD turbulence. In particular, we discuss the generation of compressible MHD waves by Alfvenic turbulence and show that this process…

Astrophysics · Physics 2016-08-30 Jungyeon Cho , A. Lazarian

The Alfvenic waves and fast magneto-sound in the relativistically hot plasmas are considered. This study is based on the novel hydrodynamic model of plasmas with the relativistic temperatures consisted of four equations for the material…

Plasma Physics · Physics 2021-08-31 Pavel A. Andreev

Using hybrid-kinetic particle-in-cell simulation, we study the evolution of an expanding, collisionless, magnetized plasma in which strong Alfv\'enic turbulence is persistently driven. Temperature anisotropy generated adiabatically by the…

High Energy Astrophysical Phenomena · Physics 2021-12-08 A. F. A. Bott , L. Arzamasskiy , M. W. Kunz , E. Quataert , J. Squire

The nonlinear response of molecular systems undergoing Markovian stochastic reorientations is calculated up to fifth order in the amplitude of the external field. Time-dependent perturbation theory is used to compute the relevant response…

Soft Condensed Matter · Physics 2018-10-10 Gregor Diezemann

Energy transfer among various spectral components of fluctuating physical parameters in plasma occurs due to the nonlinear interactions, but these effects are typically not captured by the traditional linear spectral methods. Plasma density…

We consider anisotropic magnetized cosmologies filled with conductive plasma fluid and study the implications of metric perturbations that propagate parallel to the ambient magnetic field. It is known that in the first order (linear)…

General Relativity and Quantum Cosmology · Physics 2010-10-27 A Kuiroukidis , K Kleidis , D B Papadopoulos

Alfv\'enic turbulence in space is usually imbalanced: amplitudes of waves propagating parallel and anti-parallel to the mean magnetic field $B_0$ are unequal. It is commonly accepted that the turbulence is driven by (counter-)collisions…

Space Physics · Physics 2016-11-29 Yuriy Voitenko , Johan De Keyser

Wave turbulence is the study of the long-time statistical behaviour of equations describing a set of weakly non-linear interacting waves. Such a theory, which has a natural asymptotic closure, allows us to probe the nature of turbulence…

Fluid Dynamics · Physics 2023-10-24 Sebastien Galtier

We analyze the well-posedness of an anisotropic, nonlocal diffusion equation. Establishing an equivalence between weighted and unweighted anisotropic nonlocal diffusion operators in the vein of unified nonlocal vector calculus, we apply our…

Analysis of PDEs · Mathematics 2021-01-13 Marta D'Elia , Mamikon Gulian

We study the propagation of cosmic rays (CRs) through a simulation of magnetohydrodynamic (MHD) turbulence at unprecedented resolution of $10{,}240^3$. We drive turbulence that is subsonic and super-Alfv\'enic, characterized by $\delta…

Alfv\'{e}nic component of MHD turbulence damps Alfv\'{e}nic waves. The consequences of this effect are important for many processes, from cosmic ray (CR) propagation to launching outflows and winds in galaxies and other magnetized systems.…

Astrophysics of Galaxies · Physics 2022-01-17 Alex Lazarian , Siyao Xu

A variety of studies of magnetised plasma turbulence invoke theories for the advection of a passive scalar by turbulent fluctuations. Examples include modelling the electron density fluctuations in the interstellar medium, understanding the…

Plasma Physics · Physics 2015-06-23 Joanne Mason , Stanislav Boldyrev , Fausto Cattaneo , Jean Carlos Perez

This paper investigates the nature of the MHD turbulence excited by the streaming of accelerated cosmic rays in a shock wave precursor. The two recognised regimes (non-resonant and resonant) of the streaming instability are taken into…

Astrophysics · Physics 2009-11-11 Guy Pelletier , Martin Lemoine , Alexandre Marcowith

A closed-form analytical solution is found for the nonlinear dynamics of isolated, near-threshold waves in the presence of strong scattering. The proposed solution can be useful in verifying codes across several disciplines, including…

Plasma Physics · Physics 2020-01-17 Vinicius Duarte , Nikolai Gorelenkov

The subject matter of this paper concerns anisotropic diffusion equations: we consider heat equations whose diffusion matrix have disparate eigenvalues. We determine first and second order approximations, we study the well-posedness of them…

Analysis of PDEs · Mathematics 2012-10-24 Mihai Bostan

Super-Alfv\'enic turbulence is widespread in astrophysical environments, including molecular clouds and the diffuse plasma of galaxy clusters. At large scales, magnetic fields play only a minor dynamical role; however, for sufficiently…

Astrophysics of Galaxies · Physics 2025-12-24 A. Lazarian , Yue Hu , D. Pogosyan

In the study of concavity properties of positive solutions to nonlinear elliptic partial differential equations the diffusion and the nonlinearity are typically independent of the space variable. In this paper we obtain new results aiming…

Analysis of PDEs · Mathematics 2023-09-01 Nouf Almousa , Claudia Bucur , Roberta Cornale , Marco Squassina

To comprehensively understand saturation of two-dimensional ($2$D) magnetized Kelvin-Helmholtz-instability-driven turbulence, energy transfer analysis is extended from the traditional interaction between scales to include eigenmode…

Plasma Physics · Physics 2023-07-26 B. Tripathi , A. E. Fraser , P. W. Terry , E. G. Zweibel , M. J. Pueschel , E. H. Anders
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