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Related papers: Cosmology with inhomogeneous magnetic fields

200 papers

We study the effects of inhomogeneities on the evolution of the Universe, by considering a range of cosmological models with discretized matter content. This is done using exact and fully relativistic methods that exploit the symmetries in…

General Relativity and Quantum Cosmology · Physics 2015-06-17 Timothy Clifton , Daniele Gregoris , Kjell Rosquist , Reza Tavakol

We examine the evolution of magnetic fields in an expanding fluid composed of matter and radiation with particular interest in the evolution of cosmic magnetic fields. We derive the propagation velocities and damping rates for relativistic…

Astrophysics · Physics 2009-10-28 K. Jedamzik , V. Katalinic , A. Olinto

We investigate hydromagnetic turbulence of primordial magnetic fields using magnetohydrodynamics (MHD) in an expanding universe. We present the basic, covariant MHD equations, find solutions for MHD waves in the early universe, and…

Astrophysics · Physics 2014-10-13 Axel Brandenburg , Kari Enqvist , Poul Olesen

We derive the amplification of the cosmological magnetic field associated with forming gravitational structure. The self-similar solutions of magnetohydrodynamic equations are computed both in linear and nonlinear regimes. We find that the…

Astrophysics · Physics 2009-11-10 G. Siemieniec-Ozieblo , Z. Golda

Standard dynamical system analysis of Einstein-Maxwell equation in $f(R)$ theories is considered in this work. We investigate cosmological dynamics of a uniform magnetic field in the Orthogonal Spatially Homogeneous (OSH) Bianchi type I…

General Relativity and Quantum Cosmology · Physics 2018-01-09 Xuyang Liu , Phongpichit Channuie , Daris Samart

We study the effects of a spatially homogenous magnetic field in Bianchi-I cosmological models. The cases of a pure magnetic field and two models with additional dust and a massless scalar field (stiff matter) are also considered. At the…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Roberto Casadio , Alexander Kamenshchik , Panagiotis Mavrogiannis , Polina Petriakova

We provide a fully general-relativistic treatment of cosmological perturbations in a universe permeated by a large-scale primordial magnetic field, using the Ellis-Bruni gauge-invariant formalism. The exact non-linear equations for general…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Christos G. Tsagas , John D. Barrow

We study linear cosmological perturbations in a previously introduced family of deformations of general relativity characterized by the absence of new degrees of freedom. The homogeneous and isotropic background in this class of theories is…

General Relativity and Quantum Cosmology · Physics 2010-06-08 Kirill Krasnov , Yuri Shtanov

The gravitational field equations on cosmological scales are obtained by averaging the Einstein field equations of general relativity. By assuming spatial homogeneity and isotropy on the largest scales, the local inhomogeneities affect the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. A. Coley

In this paper I review some recent, interlinked, work undertaken using cosmological perturbation theory -- a powerful technique for modelling inhomogeneities in the Universe. The common theme which underpins these pieces of work is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Adam J. Christopherson

Magnetic fields are observed not only in stars, but in galaxies, clusters, and even high redshift Lyman-alpha systems. In principle, these fields could play an important role in structure formation and also affect the anisotropies in the…

Astrophysics · Physics 2009-10-31 Roy Maartens

This paper introduces a systematic treatment of the linear theory of scalar gravitational perturbations in the presence of a fully inhomogeneous magnetic field. The analysis is conducted both in the synchronous and in the conformally…

Astrophysics · Physics 2009-11-10 Massimo Giovannini

The origin of large-scale magnetic fields in cosmic structures and the intergalactic medium is still poorly understood. We explore the effects of non-minimal couplings of electromagnetism on the cosmological evolution of currents and…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-10 Lukas Hollenstein , Rajeev Kumar Jain , Federico R. Urban

To understand the observational properties of cosmological models, in particular, the temperature of the cosmic microwave background radiation, it is necessary to study their null geodesics. Dynamical systems theory, in conjunction with the…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Ulf S Nilsson , C. Uggla , J. Wainwright

The origin of galactic and extra-galactic magnetic fields is an unsolved problem in modern cosmology. A possible scenario comes from the idea of these fields emerged from a small field, a seed, which was produced in the early universe…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-14 Hector J. Hortua , Leonardo Castaneda , Juan M. Tejeiro

In this paper we apply second-order gauge-invariant perturbation theory to investigate the possibility that the non-linear coupling between gravitational waves (GW) and a large scale inhomogeneous magnetic field acts as an amplification…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Caroline Zunckel , Gerold Betschart , Peter K S Dunsby , Mattias Marklund

We evaluate the effect of inhomogeneity energy on the expansion rate of the universe. Our method is to expand to Newtonian order in potential and velocity but to take into account fully nonlinear density inhomogeneities. To linear order in…

Astrophysics · Physics 2009-11-11 E. R. Siegel , J. N. Fry

We study the symmetries of the post-recombination cosmological magnetohydrodynamical equations which describe the evolution of dark matter, baryons and magnetic fields in a self-consistent way. This is done both at the level of fluid…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 P. Berger , A. Kehagias , A. Riotto

The evolution of three-dimensional, large-scale, magnetic fields, in a galactic disk is investigated numerically. The N-body simulations of galactic dynamics are incorporated into the kinematic calculations of induction equations to study…

Astrophysics · Physics 2007-05-23 K. Otmianowska-Mazur , S. von Linden , H. Lesch , G. Skupniewicz

In paper I, we obtained an equation for the evolution of density inhomogeneities in a radiation dominated universe when they are affected by magnetic fields. In this second paper we apply this equation to the case in which the subjacent…

Astrophysics · Physics 2016-08-30 E. Florido , E. Battaner