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Related papers: Universal Nonlinear Small-Scale Dynamo

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We investigate the overdamped dynamics of a `passive' particle driven by nonreciprocal interaction with a `driver' Brownian particle. When the interaction between them is short-ranged, the long-time behavior of the driven particle is…

Statistical Mechanics · Physics 2024-12-24 Urna Basu , P. L. Krapivsky , Satya N. Majumdar

A quasi-linear theory is presented for how randomly forced, barotropic velocity fluctuations cause an exponentially-growing, large-scale (mean) magnetic dynamo in the presence of a uniform shear flow, $\vec{U} = S x \vec{e}_y$. It is a…

Astrophysics of Galaxies · Physics 2015-05-30 James C. McWilliams

A dynamical analysis is presented that self-consistently takes into account the motion of the critical layer, in which the magnetic field reconnects, to describe how the m=n=1 resistive internal kink mode develops in the nonlinear regime.…

Plasma Physics · Physics 2009-11-10 Marie-Christine Firpo , Bruno Coppi

Using a rotating flat layer heated from below as an example, we consider effects which lead to stabilizing an exponentially growing magnetic field in magnetostrophic convection in transition from the kinematic dynamo to the full non-linear…

Fluid Dynamics · Physics 2015-05-18 P. Hejda , M. Reshetnyak

The stability of the ideal magnetohydrodynamic (MHD) interchange mode at marginal conditions is studied. A sufficiently strong constant magnetic field component transverse to the direction of mode symmetry provides the marginality…

Plasma Physics · Physics 2012-11-26 Jupiter Bagaipo , P. N. Guzdar , A. B. Hassam

We demonstrate that the critical magnetic Reynolds number $Rm_c$ for a turbulent non-helical dynamo in the low magnetic Prandtl number $Pm$ limit (i.e. $Pm = Rm/Re \ll 1$) can be significantly reduced if the flow is submitted to global…

Fluid Dynamics · Physics 2017-06-28 Kannabiran Seshasayanan , Vassilios Dallas , Alexandros Alexakis

In this paper, we establish the global well-posedness of the incompressible magnetohydrodynamics (MHD) system on $n-$dimensional $(n\geq 2)$ periodic boxes with either no magnetic diffusivity (non-resistive case) or no fluid viscosity…

Analysis of PDEs · Mathematics 2026-02-05 Quansen Jiu , Yaowei Xie , Zhihong Yan

It has been recently shown numerically that a small-scale dynamo (SSD) instability could be possible in solar-like low magnetic Prandtl number plasmas. It has been proposed that the presence of SSD can potentially have a significant impact…

Solar and Stellar Astrophysics · Physics 2025-04-09 Jörn Warnecke , Maarit J. Korpi-Lagg , Matthias Rheinhard , Mariangela Viviani , Ameya Prabhu

We construct and study global solutions for the 3-dimensional incompressible MHD systems with arbitrary small viscosity. In particular, we provide a rigorous justification for the following dynamical phenomenon observed in many contexts:…

Analysis of PDEs · Mathematics 2016-03-29 Ling-Bing He , Li Xu , Pin Yu

We examine a simple theoretical model to estimate (by fine tuning condition) the value of the cosmological constant. We assume, in analogy with holographic principle, that cosmological constant, like classical surface tension coefficient in…

Astrophysics · Physics 2008-01-21 V. Pankovic , S. Ciganovic , J. Ivanovic , R. Glavatovic , P. Grujic

Weakly-collisional plasmas, such as the solar wind or the intra-cluster medium (ICM) of galaxy clusters, evolve in the presence of dynamically strong magnetic fields. The turbulent dynamo can amplify magnetic fields to such levels by…

Astrophysics of Galaxies · Physics 2025-02-11 Radhika Achikanath Chirakkara , Christoph Federrath , Amit Seta

We consider the backreaction of the magnetic field on the magnetic dynamo coefficients and the role of boundary conditions in interpreting whether numerical evidence for suppression is dynamical. If a uniform field in a periodic box serves…

Astrophysics · Physics 2009-10-31 Eric G. Blackman , George B. Field

We prove a concise and easily verifiable criterion on the existence and global stability of stationary solutions for random dynamical systems (RDSs). As a consequence, we can show that the $\omega$-limit sets of all pullback trajectories of…

Dynamical Systems · Mathematics 2025-08-13 Xiang Lv

We demonstrate that a magneto-convection simulation incorporating essential physical processes governing solar surface convection exhibits turbulent small-scale dynamo action. By presenting a derivation of the energy balance equation and…

Solar and Stellar Astrophysics · Physics 2010-04-23 Jonathan Pietarila Graham , Robert Cameron , Manfred Schuessler

Recent experiments and simulations have shown that unsteady turbulent flows, before reaching a dynamic equilibrium state, display a universal behaviour. We show that the observed universal non-equilibrium scaling can be explained using a…

Fluid Dynamics · Physics 2017-03-08 Wouter Bos , Robert Rubinstein

A wide variety of astrophysical phenomena involve the flow of turbulent magnetized gas with relativistic velocity or energy density. Examples include gamma-ray bursts, active galactic nuclei, pulsars, magnetars, micro-quasars, merging…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Jonathan Zrake , Andrew MacFadyen

We suggest a new mean field dynamo model in anomalous MagnetoHydroDynamics (AMHD) accounting for the mean spin (polarization) of the magnetized chiral (ultrarelativistic) plasma of a neutron star (NS). For simplicity we consider a…

High Energy Astrophysical Phenomena · Physics 2020-04-03 Maxim Dvornikov , V. B. Semikoz , D. D. Sokoloff

We consider the problem of incompressible, forced, nonhelical, homogeneous, isotropic MHD turbulence with no mean magnetic field. This problem is essentially different from the case with externally imposed uniform mean field. There is no…

Astrophysics · Physics 2008-11-26 A. A. Schekochihin , S. C. Cowley , S. F. Taylor , J. L. Maron , J. C. McWilliams

We consider the ideal magnetohydrodynamics (MHD) of a shallow fluid layer on a rapidly rotating planet or star. The presence of a background toroidal magnetic field is assumed, and the "shallow water" beta-plane approximation is used. We…

Earth and Planetary Astrophysics · Physics 2015-06-22 Alexander M. Balk

Understanding the in situ amplification of large scale magnetic fields in turbulent astrophysical rotators has been a core subject of dynamo theory. When turbulent velocities are helical, large scale dynamos that substantially amplify…

Fluid Dynamics · Physics 2012-06-22 Jonathan Pietarila Graham , Eric G. Blackman , Pablo D. Mininni , Annick Pouquet