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Related papers: Small-scale dynamo with finite correlation times

200 papers

Ferrofluids are a class of materials that exhibit both fluid and magnetic properties. We consider a two-phase diffuse interface model for the dynamics of ferrofluids on a bounded domain. One phase is assumed to be magnetic, the other phase…

Analysis of PDEs · Mathematics 2025-07-08 Samuel Lanthaler , Franziska Weber

An analytical theory of wave turbulence is developed for pure compressible magnetohydrodynamics in the small $\beta$ limit. In contrast to previous works where the multiple scale method was not mentioned and slow magneto-acoustic waves were…

Plasma Physics · Physics 2023-04-19 Sebastien Galtier

This paper concerns the global-in-time evolution of a generic compressible two-fluid model in $\mathbb{R}^d$ ($d\geq3$) with the common pressure law. Due to the non-dissipative properties for densities and two different particle paths…

Analysis of PDEs · Mathematics 2025-02-11 Ling-Yun Shou , Jiayan Wu , Lei Yao , Yinghui Zhang

The magnetic field measured in the Madison Dynamo Experiment shows intermittent periods of growth when an axial magnetic field is applied. The geometry of the intermittent field is consistent with the fastest growing magnetic eigenmode…

Plasma Physics · Physics 2009-11-11 M. D. Nornberg , E. J. Spence , R. D. Kendrick , C. M. Jacobson , C. B. Forest

The study of dynamo action in astrophysical objects classically involves two timescales: the slow diffusive one and the fast advective one. We investigate the possibility of field amplification on an intermediate timescale associated with…

Classical Physics · Physics 2009-11-13 Emmanuel Dormy , David Gerard-Varet

It is remarkable that the primordial fluctuations as revealed by the CMB coincide with what quantum fluctuations would look like if they were stretched across the sky by accelerated cosmic expansion. It has been observed that this same…

High Energy Physics - Theory · Physics 2021-05-26 C. P. Burgess , S. P. de Alwis , F. Quevedo

{\em Voyager 1} and {\em 2} data reveals that magnetic field fluctuations are compressive and exhibit a Gaussian distribution in the compressed heliosheath plasma, whereas they follow a lognormal distribution in a nearly incompressible…

Space Physics · Physics 2015-05-18 Dastgeer Shaikh

Several recent advances in turbulent dynamo theory are reviewed. High resolution simulations of small-scale and large-scale dynamo action in periodic domains are compared with each other and contrasted with similar results at low magnetic…

Solar and Stellar Astrophysics · Physics 2012-07-10 Axel Brandenburg , Dmitry Sokoloff , Kandaswamy Subramanian

This paper extends our earlier approach [cf. Phys. Plasmas 17, 032503 (2010), 23, 022308 (2016)] to obtaining a priori bounds on enstrophy in neutral fluids (R-Euler) and ideal magnetohydrodynamics (R-MHD). This results in a far-reaching…

Plasma Physics · Physics 2018-03-06 Govind S. Krishnaswami , Sonakshi Sachdev , Anantanarayanan Thyagaraja

We show that the maximal globally hyperbolic development of near-FLRW initial data for the Einstein scalar-field Vlasov system exhibits stable Big Bang formation in the collapsing direction. The solutions exhibit stable Kretschmann scalar…

General Relativity and Quantum Cosmology · Physics 2025-05-27 David Fajman , Liam Urban

This paper is the fourth in a series exploring the physical consequences of the solidity of highly viscous liquids. It is argued that the two basic characteristics of a flow event (a jump between two energy minima in configuration space)…

Soft Condensed Matter · Physics 2007-05-23 Jeppe C. Dyre

We consider the macroscopic limit for the space-time density fluctuations in the open symmetric simple exclusion in the quasi-static scaling limit. We prove that the distribution of these fluctuations converge to a gaussian space-time field…

Probability · Mathematics 2024-01-09 C. Bernardin , P. Gonçalves , S. Olla

We numerically demonstrate the feasibility of kinematic fast dynamos for a class of time-periodic axisymmetric flows of conducting fluid confined inside a sphere. The novelty of our work is in considering the realistic flows, which are…

Plasma Physics · Physics 2013-09-19 I. V. Khalzov , C. M. Cooper , C. B. Forest

We study a system of backscattering hard rods in one dimension. Contrary to the usual ballistic hard rods, these hard rods flip the sign of their velocities with a rate $\gamma$. This leads to the decay of the odd moments of velocity while…

Statistical Mechanics · Physics 2026-05-29 Mrinal Jyoti Powdel

Intermittent large-scale high-shear flows are found to occur frequently and spontaneously in direct numerical simulations of statistically stationary turbulent Boussinesq magnetohydrodynamic (MHD) convection. The energetic steady-state of…

Solar and Stellar Astrophysics · Physics 2013-09-06 J. Pratt , A. Busse , W. -C. Mueller

We study, using numerical simulations, the dynamical evolution of self-gravitating point particles in static euclidean space, starting from a simple class of infinite ``shuffled lattice'' initial conditions. These are obtained by applying…

Statistical Mechanics · Physics 2008-11-26 Thierry Baertschiger , Michael Joyce , Andrea Gabrielli , Francesco Sylos Labini

Flow-induced instabilities are relevant for the storage and dynamics of magnetic fields in stellar convection zones and possibly also in other astrophysical contexts. We continue the study started in the first paper of this series by…

Astrophysics · Physics 2009-11-13 V. Holzwarth , D. Schmitt , M. Schuessler

We present technical results required for the description and understanding of correlations and fluctuations of the empirical density and current as well as diverse time-integrated and time-averaged thermodynamic currents of diffusion…

Statistical Mechanics · Physics 2023-01-09 Cai Dieball , Aljaž Godec

The recently proposed dynamical effective field model (DEFM) is quantitatively accurate for describing dynamical magnetic response of ferrofluids. In paper I it is derived under the framework of dynamical density functional theory, via…

Soft Condensed Matter · Physics 2020-11-17 Angbo Fang

In this paper we study the Hamiltonian dynamics of charged particles subject to a non-self-consistent stochastic electric field, when the plasma is in the so-called weak turbulent regime. We show that the asymptotic limit of the Vlasov…

Analysis of PDEs · Mathematics 2021-10-13 Claude Bardos , Nicolas Besse