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Related papers: Cosmology with inhomogeneous magnetic fields

200 papers

We study inhomogeneous magnetised cosmologies through the post-recombination era in the framework of Newtonian gravity and the ideal-magnetohydrodynamic limit. The nonlinear kinematic and dynamic equations are derived and linearised around…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-02 Hera Vasileiou , Christos G. Tsagas

We study the time evolution of magnetic fields in various configurations of spatially inhomogeneous pseudoscalar fields, which are the coherent superposition of axions. The new induction equation for the magnetic field, which accounts for…

High Energy Physics - Phenomenology · Physics 2024-04-02 Petr Akhmetiev , Maxim Dvornikov

This article looks at how inhomogeneous spacetime models may be significant for cosmology. First it looks at how the averaging process may affect large scale dynamics, with backreaction effects leading to effective contributions to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 George F R Ellis

Assuming a large-scale homogeneous magnetic field, we follow the covariant and gauge-invariant approach used by Tsagas and Barrow to describe the evolution of density and magnetic field inhomogeneities and curvature perturbations in a…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Stacey Hobbs , Peter K. S. Dunsby

The excitation of cosmological perturbations in an anisotropic cosmological model and in the presence of a homogeneous magnetic field has been studied, using the ideal magnetohydrodynamic (MHD) equations. In this case, the system of partial…

Astrophysics · Physics 2009-06-23 K. Kleidis , A. Kuiroukidis , D. B. Papadopoulos , L. Vlahos

We review the study of inhomogeneous perturbations about a homogeneous and isotropic background cosmology. We adopt a coordinate based approach, but give geometrical interpretations of metric perturbations in terms of the expansion, shear…

Astrophysics · Physics 2010-04-23 Karim A. Malik , David Wands

We develop further our extension of the Ellis-Bruni covariant and gauge-invariant formalism to the general relativistic treatment of density perturbations in the presence of cosmological magnetic fields. We present detailed analysis of the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Christos G. Tsagas , John D. Barrow

We discuss how a cosmological magnetic field could affect the expansion of the universe, through its interaction with the spacetime geometry. The tension of the field lines means that the magneto-curvature coupling tends to accelerate…

Astrophysics · Physics 2009-10-31 D. R. Matravers , C. G. Tsagas

It has been recently proposed that the presence of a temporal electromagnetic field on cosmological scales could explain the phase of accelerated expansion that the universe is currently undergoing. The field contributes as a cosmological…

General Physics · Physics 2009-11-13 Jose Beltran Jimenez , Tomi S. Koivisto , Antonio L. Maroto , David F. Mota

In this paper, we have investigated the density perturbations and cosmological evolution in the FLRW universe in presence of a cosmic magnetic field, which may be assumed to mimic primordial magnetic fields. Such magnetic fields have…

High Energy Physics - Theory · Physics 2025-08-11 Samarjit Chakraborty , Sarbari Guha

In this thesis we investigate cosmological models more general than the isotropic and homogeneous Friedmann-Lemaitre models. We focus on cosmologies with one spatial degree of freedom, whose matter content consists of a perfect fluid and…

General Relativity and Quantum Cosmology · Physics 2009-09-29 Woei Chet Lim

We consider that no mean magnetic field exists during this epoch, but that there is a mean magnetic energy associated with large-scale magnetic inhomogeneities. We study the evolution of these inhomogeneities and their influence on the…

Astrophysics · Physics 2009-01-14 E. Battaner , E. Florido , J. Jimenez-Vicente

We study the system of interacting axions and magnetic fields in the early universe after the quantum chromodynamics phase transition, when axions acquire masses. Both axions and magnetic fields are supposed to be spatially inhomogeneous.…

High Energy Physics - Phenomenology · Physics 2022-04-11 Maxim Dvornikov

We study the linear evolution of magnetised cosmological perturbations in the post-recombination epoch. Using full general relativity and adopting the ideal magnetohydrodynamic approximation, we refine and extend the previous treatments.…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Dimitra Tseneklidou , Christos G. Tsagas , John D. Barrow

This paper concerns the generation and evolution of the cosmological (large-scale $\sim Mpc$) magnetic fields in an inflationary universe. The universe during inflation is represented by de Sitter space-time. We started with the Maxwell…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Zuxiang Dai

We consider the evolution of electromagnetic fields in curved spacetimes and calculate the exact wave equations of the associated electric and magnetic components. Our analysis is fully covariant, applies to a general spacetime and isolates…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Christos G. Tsagas

We study the evolution of cosmological perturbations, using a hybrid approximation scheme which upgrades the weak-field limit of Einstein's field equations to account for post-Newtonian scalar and vector metric perturbations and for…

Astrophysics · Physics 2007-05-23 Carmelita Carbone , Sabino Matarrese

A large-scale cosmic magnetic field affects not only the growth of density perturbations, but also rotational instabilities and anisotropic deformation in the density distribution. We give a fully relativistic treatment of all these…

Astrophysics · Physics 2008-11-26 Christos Tsagas , Roy Maartens

We study the evolution of magnetic fields in turbulent hot plasma of the early Universe accounting for the chiral magnetic effect. The magnetohydrodynamic turbulence is modeled by replacing the matter velocity in the advection term in the…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-17 Maxim Dvornikov

Astrophysical observations provide a picture of the universe as a 4-dim homogeneous and isotropic flat space-time dominated by an unknown form of dark energy. To achieve such a cosmology one has to consider in the early universe an…

Astrophysics · Physics 2009-11-10 F. Canfora , A. Troisi
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