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Related papers: Exploring helical dynamos with machine learning

200 papers

The Eulerian space-time correlation of strong Magnetohydrodynamic (MHD) turbulence in strongly magnetized plasmas is investigated by means of direct numerical simulations of Reduced MHD turbulence and phenomenological modeling. Two new…

Solar and Stellar Astrophysics · Physics 2020-04-27 Jean C. Perez , Sofiane Bourouaine

Markov chain Monte Carlo (MCMC) algorithms offer various strategies for sampling; the Hamiltonian Monte Carlo (HMC) family of samplers are MCMC algorithms which often exhibit improved mixing properties. The recently introduced magnetic HMC,…

Machine Learning · Statistics 2020-10-16 James A. Brofos , Roy R. Lederman

Machine learning force fields (MLFFs) are powerful tools for materials modeling, but their performance is often limited by training dataset quality, particularly the lack of rare event configurations. This limitation undermines their…

Materials Science · Physics 2025-04-23 Zihan Yan , Zheyong Fan , Yizhou Zhu

We study in the present paper how Hall effect modifies the quenching process of the electromotive force (e.m.f.) in Mean Field Dynamo (MFD) theories. We write down the evolution equations for the e.m.f. and for the large and small scale…

Astrophysics · Physics 2009-11-11 A. Kandus , M. J. Vasconcelos , A. H. Cerqueira

We give a short introduction to the subject and review advances in understanding the basic ingredients of the mean-field dynamo theory. The discussion includes the recent analytic and numerical work in developments for the mean…

Solar and Stellar Astrophysics · Physics 2015-06-12 V. V. Pipin

Modeling and forecasting the solar wind-driven global magnetic field perturbations is an open challenge. Current approaches depend on simulations of computationally demanding models like the Magnetohydrodynamics (MHD) model or sampling…

We explore the suitability of deep learning to capture the physics of subgrid-scale ideal magnetohydrodynamics turbulence of 2-D simulations of the magnetized Kelvin-Helmholtz instability. We produce simulations at different resolutions to…

Computational Physics · Physics 2020-08-27 Shawn G. Rosofsky , E. A. Huerta

A fully three-dimensional (3D) magnetohydrodynamical (MHD) model is applied to simulate the evolution of the large-scale magnetic field in cluster galaxies interacting with the intra-cluster medium (ICM). As the model input we use a time…

Astrophysics · Physics 2011-05-23 K. Otmianowska-Mazur , B. Vollmer

We report the development of a hybrid numerical / analytical model capable of mapping the spatially-varying distributions of the local ferromagnetic resonance (FMR) frequency and dynamic magnetic susceptibility in a wide class of patterned…

Mesoscale and Nanoscale Physics · Physics 2019-05-29 C. S. Davies , V. D. Poimanov , V. V. Kruglyak

Magnetohydrodynamic (MHD) turbulence on a $\beta$-plane with an in-plane mean field, a system which serves as a simple model for the solar tachocline, is investigated analytically and computationally. We first derive two useful analytic…

Plasma Physics · Physics 2022-12-12 R. A. Heinonen , P. H. Diamond , M. F. D. Katz , G. E. Ronimo

Left- and right-handed helical modes' statistical absolute equilibria appear \textit{separately}. If both chiral sectors present, one can dominate around its positive pole, which is relevant to the nearly maximally helical (force free for…

Chaotic Dynamics · Physics 2014-08-01 Jian-Zhou Zhu , Weihong Yang , Guang-Yu Zhu

We study the effect of a magnetic field on the behaviour of a conducting elastic rod subject to a novel set of boundary conditions that, in the case of a transversely isotropic rod, give rise to exact helical post-buckling solutions. The…

Dynamical Systems · Mathematics 2015-06-04 J. Valverde , G. H. M. van der Heijden

The amplification of magnetic fields is crucial for understanding the observed magnetization of stars and galaxies. Turbulent dynamo is the primary mechanism responsible for that but the understanding of its action in a collapsing…

Astrophysics of Galaxies · Physics 2026-04-22 Muhammed Irshad P , Pallavi Bhat , Kandaswamy Subramanian , Anvar Shukurov

In this article, several aspects of the dynamics of a toy model for longrange Hamiltonian systems are tackled focusing on linearly unstable unmagnetized (i.e. force-free) cold equilibria states of the Hamiltonian Mean Field (HMF). For…

Mathematical Physics · Physics 2013-05-20 Wahb Ettoumi , Marie-Christine Firpo

Models for GRB outflows invoke turbulence in relativistically hot magnetized fluids. In order to investigate these conditions we have performed high-resolution three-dimensional numerical simulations of relativistic magneto-hydrodynamical…

High Energy Astrophysical Phenomena · Physics 2011-09-29 Jonathan Zrake , Andrew MacFadyen

Energy based models (EBMs) are appealing due to their generality and simplicity in likelihood modeling, but have been traditionally difficult to train. We present techniques to scale MCMC based EBM training on continuous neural networks,…

Machine Learning · Computer Science 2020-07-01 Yilun Du , Igor Mordatch

Accurate subgrid-scale turbulence models are needed to perform realistic numerical magnetohydrodynamic (MHD) simulations of the subsurface flows of the Sun. To perform large-eddy simulations (LES) of turbulent MHD flows, three unknown terms…

Solar and Stellar Astrophysics · Physics 2010-10-28 G. Balarac , A. G. Kosovichev , O. Brugière , A. A. Wray , N. N. Mansour

Accurate prediction of atmospheric optical turbulence in localized environments is essential for estimating the performance of free-space optical systems. Macro-meteorological models developed to predict turbulent effects in one environment…

Atmospheric and Oceanic Physics · Physics 2023-10-30 Christopher Jellen , Charles Nelson , John Burkhardt , Cody Brownell

This is a brief review of the main results of our recent studies of the nonlinear evolution of the small-scale MHD dynamo in the high-Prandtl-number regime and of the structure of the resulting saturated state of the isotropic homogeneous…

Astrophysics · Physics 2007-05-23 A. A. Schekochihin , S. C. Cowley , G. W. Hammett , J. L. Maron , J. C. McWilliams

The mean electromotive force in the framework of mean--field magnetohydrodynamics is found with a particular attention to the effect of a mean rotation of the fluid on the mean electromotive force. Anisotropy of the turbulence due to…

Astrophysics · Physics 2009-11-07 K-H. Raedler , N. Kleeorin , I. Rogachevskii