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Related papers: The magneto-geostrophic equations: a survey

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The geodesic equation encodes test-particle dynamics at arbitrary gravitational coupling, hence retaining all orders in the post-Minkowskian (PM) expansion. Here we explore what geodesic motion can tell us about dynamical scattering in the…

High Energy Physics - Theory · Physics 2021-01-20 Clifford Cheung , Nabha Shah , Mikhail P. Solon

We test the ability of large scale velocity fields inferred from geomagnetic secular variation data to produce the global magnetic field of the Earth.Our kinematic dynamo calculations use quasi-geostrophic (QG) flows inverted from…

Geophysics · Physics 2016-01-20 Nathanaël Schaeffer , Estelina Lora Silva , Maria Alexandra Pais

The dynamics of a membrane is a coupled system comprising a moving elastic surface and an incompressible membrane fluid. We will consider a reduced elastic surface model, which involves the evolution equations of the moving surface, the…

Analysis of PDEs · Mathematics 2015-05-27 Wei Wang , Pingwen Zhang , Zhifei Zhang

Turbulence is the most common state of astrophysical flows. In typical astrophysical fluids, turbulence is accompanied by strong magnetic fields, which has a large impact on the dynamics of the turbulent cascade. Recently, there has been a…

Astrophysics · Physics 2011-05-10 Jungyeon Cho , A. Lazarian , Ethan Vishniac

Quantum geometrodynamics is canonical quantum gravity with the three-metric as the configuration variable. Its central equation is the Wheeler--DeWitt equation. Here I give an overview of the status of this approach. The issues discussed…

General Relativity and Quantum Cosmology · Physics 2009-04-17 Claus Kiefer

The long-term dynamics of the geostationary Earth orbits (GEO) is revisited through the application of canonical perturbation theory. We consider a Hamiltonian model accounting for all major perturbations: geopotential at order and degree…

Earth and Planetary Astrophysics · Physics 2017-01-02 Fabien Gachet , Alessandra Celletti , Giuseppe Pucacco , Christos Efthymiopoulos

In a first approximation, the Earth's interior has an isotropic structure with a spherical symmetry. Over the last decades the geophysical observations have revealed, at different spatial scales, the existence of several perturbations from…

Geophysics · Physics 2014-02-27 Calin Vamos , Nicolae Suciu

We perform a test of John Moffat's Modified Gravity theory (MOG) within the Milky Way, adopting the well known "Rotation Curve" method. We use the dynamics of observed tracers within the disk to determine the gravitational potential as a…

Astrophysics of Galaxies · Physics 2018-12-10 Carolina Negrelli , Maria Benito , Susana Landau , Fabio Iocco , Lucila Kraiselburd

Magnetohydrodynamic turbulence affects both terrestrial and astrophysical plasmas. The properties of magnetized turbulence must be better understood to more accurately characterize these systems. This work presents ideal MHD simulations of…

Fluid Dynamics · Physics 2021-04-28 Forrest W. Glines , Philipp Grete , Brian W. O'Shea

The first estimation of the energy cascade rate ${|\epsilon_C|}$ of magnetosheath turbulence is obtained using the CLUSTER and THEMIS spacecraft data and an exact law of compressible isothermal magnetohydrodynamics turbulence.…

Space Physics · Physics 2018-02-07 Lina Hadid , Fouad Sahraoui , Sebastien Galtier , Shiyong Huang

This paper contains a review of the theory and practice of gravitomagnetism, with particular attention to the different and numerous proposals which have been put forward to experimentally or observationally verify its effects. The basics…

General Relativity and Quantum Cosmology · Physics 2010-11-11 Matteo Luca Ruggiero , Angelo Tartaglia

Direct numerical simulations of decaying and forced magnetohydrodynamic (MHD) turbulence without and with mean magnetic field are analyzed by higher-order two-point statistics. The turbulence exhibits statistical anisotropy with respect to…

Plasma Physics · Physics 2009-11-10 Wolf-Christian Mueller , Dieter Biskamp , Roland Grappin

The chaotical dynamics is studied in different Friedmann-Robertson- Walker cosmological models with scalar (inflaton) field and hydrodynamical matter. The topological entropy is calculated for some particular cases. Suggested scheme can be…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. Yu. Kamenshchik , I. M. Khalatnikov S. V. Savchenko , A. V. Toporensky

The normal field instability in magnetic liquids is investigated experimentally by means of a radioscopic technique which allows a precise measurement of the surface topography. The dependence of the topography on the magnetic field is…

Pattern Formation and Solitons · Physics 2015-06-26 C. Gollwitzer , G. Matthies , R. Richter , I. Rehberg , L. Tobiska

We investigate insterstellar gas spheres by determining the metric functions, the material distribution, and the features of particle orbits in terms of stability and geodesics. An exact solution of the Einstein's equations for interstellar…

General Relativity and Quantum Cosmology · Physics 2017-08-21 Dániel Barta

Global dynamo simulations solving the equations of magnetohydrodynamics (MHD) have been a tool of astrophysicists who try to understand the magnetism of the Sun for several decades now. During recent years many fundamental issues in dynamo…

Solar and Stellar Astrophysics · Physics 2011-07-08 P. J. Käpylä

The paper presents results for deriving closed-form analytic solutions of the evolution of inhomogeneities in a homogeneous spatially flat multicomponent cosmological model. Mathematical methods to derive computable forms of the…

Classical Analysis and ODEs · Mathematics 2016-09-06 Hans J. Haubold , Arak Mathai Mathai

Spatiotemporal correlation of magnetic field fluctuations is investigated using the Magnetospheric Multiscale mission in the terrestrial magnetosheath. The first observation of the turbulence propagator in space emerges through analysis of…

We consider general curvature-invariant modifications of the Einstein-Hilbert action that become important only in regions of extremely low space-time curvature. We investigate the far future evolution of the universe in such models,…

Turbulence is the most common state of astrophysical flows. In typical astrophysical fluids, turbulence is accompanied by strong magnetic fields, which has a large impact on the dynamics of the turbulent cascade. Recently, there has been a…

Astrophysics · Physics 2007-05-23 A. Lazarian , Jungyeon Cho , Huirong Yan