English
Related papers

Related papers: Universal Nonlinear Small-Scale Dynamo

200 papers

We present the results of two empirical constancies: the fine structure constant and the Rydberg constant. When the speed of light c is taken away from the fine structure constant, as shown elsewhere, this constancy implies the constancy of…

General Physics · Physics 2009-09-30 Antonio Alfonso-Faus

The axisymmetric kinematic dynamo problem is reconsidered and a number of open questions are answered. Apart from axisymmetry and smoothness of data and solution we deal with this problem under quite general conditions, i.e. we assume a…

Solar and Stellar Astrophysics · Physics 2019-09-30 Ralf Kaiser , Andreas Tilgner

A short distance expansion method (SDE) that is well known in the quantum field theory for analysis of turbulent behaviour of stochastic magnetic hydrodynamics of incompressible conductive fluid is applied. As a result is shown that in an…

chao-dyn · Physics 2016-08-31 Wolchenkov Dmitriy

The magnetic Rayleigh-Taylor instability has been shown to play a key role in many astrophysical systems. The equation for the growth rate of this instability in the incompressible limit, and the most-unstable mode that can be derived from…

Solar and Stellar Astrophysics · Physics 2016-10-27 Andrew Hillier

Supernovae are the dominant energy source for driving turbulence within the interstellar plasma. Until recently, their effects on magnetic field amplification in disk galaxies remained a matter of speculation. By means of self-consistent…

Astrophysics · Physics 2009-11-13 Oliver Gressel , Udo Ziegler , Detlef Elstner , Günther Rüdiger

In this manuscript using the asymptotic method of multiscale nonlinear theory we construct a nonlinear theory of the appearance of large-scale structures in the stratified conductive medium with the presence of small-scale oscillations of…

Earth and Planetary Astrophysics · Physics 2016-12-30 M. I. Kopp , A. V. Tur , V. V. Yanovsky

We present experimental and theoretical results addressing the Reynolds number (Re) dependence of drag reduction by sufficiently large concentrations of rod-like polymers in turbulent wall-bounded flows. It is shown that when Re is small…

Chaotic Dynamics · Physics 2007-05-23 Yacine Amarouchene , Daniel Bonn , Hamid Kellay , Ting-Shek Lo , Victor S. L'vov , Itamar Procaccia

We investigate the transfer of energy from large scales to small scales in fully developed forced three-dimensional MHD-turbulence by analyzing the results of direct numerical simulations in the absence of an externally imposed uniform…

Fluid Dynamics · Physics 2015-06-26 Alexandros Alexakis , Pablo D. Mininni , Annick Pouquet

This paper is a detailed report on a programme of simulations used to settle a long-standing issue in the dynamo theory and demonstrate that the fluctuation dynamo exists in the limit of large magnetic Reynolds number Rm>>1 and small…

We re-examine the nature of the turbulent magnetic diffusivity tensor of mean field electrodynamics and show that an inconsistency arises if it is calculated via consideration of time-independent magnetic fields. Specifically, the predicted…

Solar and Stellar Astrophysics · Physics 2010-01-14 David W. Hughes , Michael R. E. Proctor

We numerically examine dynamo action generated by a flow of an electrically conducting fluid in a precessing cylindrical cavity. We compare a simplified kinematic approach based on the solution of the magnetic induction equation with a…

Fluid Dynamics · Physics 2025-04-07 André Giesecke , Mike Wilbert , Ján Šimkanin , Rainer Grauer , Frank Stefani

We study the monotone nonlinear energy stability of \textit{magnetohydrodynamics plane shear flows, Couette and Hartmann flows}. We prove that the least stabilizing perturbations, in the energy norm, are the two-dimensional spanwise…

Mathematical Physics · Physics 2023-07-10 Giuseppe Mulone

We study the properties of fundamental physical constants using the threefold classification of dimensional constants proposed by J.-M. L{\'e}vy-Leblond: constants of objects (masses, etc.), constants of phenomena (coupling constants), and…

General Relativity and Quantum Cosmology · Physics 2020-10-02 A. A. Sheykin , S. N. Manida

In electromagnetism, the vacuum impedance $Z_0$ is a universal constant, which is as important as the velocity of light $c$ in vacuum. Unfortunately, however, its significance does not seem to be appreciated so well and sometimes the…

General Physics · Physics 2016-03-24 Masao Kitano

In this paper, we consider the full compressible, viscous, non-resistive MHD system under the assumption that the fluids move on a plane while the magnetic field is oriented vertically. Within the framework of Besov spaces, by introducing…

Analysis of PDEs · Mathematics 2024-08-15 Xiaoping Zhai , Shunhang Zhang

The growth rate of the dynamo instability as a function of the magnetic Reynolds number Rm is investigated by means of numerical simulations for the family of the ABC flows and for 2 different forcing scales. For the ABC flows that are…

Fluid Dynamics · Physics 2015-05-28 Alexandros Alexakis

We prove the local wellposedness of the Cauchy problems for the electron magnetohydrodynamics equations (E-MHD) without resistivity for possibly large perturbations of nonzero uniform magnetic fields. While the local wellposedness problem…

Analysis of PDEs · Mathematics 2024-02-12 In-Jee Jeong , Sung-Jin Oh

Mean-field dynamo theory suggests that turbulent convection in a rotating layer of electrically-conducting fluid produces a significant alpha-effect, which is one of the key ingredients in any mean-field dynamo model. Provided that this…

Solar and Stellar Astrophysics · Physics 2014-01-06 Benjamin Favier , Paul J. Bushby

Theories with ingredients like the Higgs mechanism, gravitons, and inflaton fields rejuvenate the idea that relativistic kinematics is dynamically emergent. Eternal inflation treats the Hubble constant H as depending on location.…

General Relativity and Quantum Cosmology · Physics 2015-05-19 Sascha Vongehr

In this paper we develop a framework for studying unstratified, magnetised eccentric discs and compute uniformly precessing eccentric modes in a cylindrical annulus which provide convenient initial conditions for numerical simulations. The…

High Energy Astrophysical Phenomena · Physics 2023-09-18 Elliot M. Lynch , Janosz W. Dewberry
‹ Prev 1 8 9 10 Next ›