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Related papers: Magnetic amplification in cylindrical cosmological…

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It is typically assumed that the kinetic and magnetic helicities play a crucial role in the growth of large-scale dynamo. In this paper we demonstrate that helicity is not essential for the amplification of large-scale magnetic field. For…

Fluid Dynamics · Physics 2017-08-22 Rohit Kumar , Mahendra K. Verma

This paper examines the generation of seed magnetic fields due to the growth of cosmological perturbations. In the radiation era, different rates of scattering from photons induce local differences in the ion and electron density and…

Astrophysics · Physics 2008-11-26 E. R. Siegel , J. N. Fry

We have performed magnetohydrodynamical simulations to study the amplification of magnetic fields in the precursors of shock waves. Strong magnetic fields are required in the precursors of the strong shocks that occur in supernova remnants.…

High Energy Astrophysical Phenomena · Physics 2015-06-17 M. Bruggen

We investigate an intensification mechanism for the magnetic field near the base of the solar convection zone that does not rely on differential rotation. Such mechanism in addition to differential rotation has been suggested by studies of…

Solar and Stellar Astrophysics · Physics 2015-06-11 H. Hotta , M. Rempel , T. Yokoyama

Observations indicate that intergalactic magnetic fields have amplitudes of the order of $\sim 10^{-6}$ G and are uniform on scales of $\sim 10$ kpc. Despite their wide presence in the Universe, their origin remains an open issue. Even by…

General Relativity and Quantum Cosmology · Physics 2022-10-26 S. Capozziello , A. Carleo , G. Lambiase

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

The origin of large scale cosmological magnetic fields remains a mystery, despite the continuous efforts devoted to that problem. We present a new model of magnetic field generation, based on local charge separation provided by an…

Astrophysics · Physics 2009-04-16 Mathieu Langer , Jean-Loup Puget , Nabila Aghanim

The magnetic helicity has paramount significance in nonlinear saturation of galactic dynamo. We argue that the magnetic helicity conservation is violated at the lepton stage in the evolution of early Universe. As a result, a cosmological…

Astrophysics · Physics 2009-11-10 V. B. Semikoz , D. D. Sokoloff

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

A late time asymptotic perturbative analysis of curvature coupled complex scalar field models with accelerated cosmological expansion is carried out on the level of formal power series expansions. For this, algebraic analogues of the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Roger Bieli

We consider cosmological models in which the cosmology is related via analytic continuation to a Euclidean asymptotically AdS planar wormhole geometry defined holographically via a pair of three-dimensional Euclidean CFTs. We argue that…

High Energy Physics - Theory · Physics 2023-06-28 Stefano Antonini , Petar Simidzija , Brian Swingle , Mark Van Raamsdonk

Using a generally covariant Electro-Vortic (magnetofluid) formalism for relativistic plasmas, the dynamical evolution of a generalized vorticity (a combination of the magnetic and kinematic parts) is studied in a cosmological context. We…

Plasma Physics · Physics 2019-05-22 Felipe A. Asenjo , Swadesh M. Mahajan

Observations are inconsistent with a homogeneous and isotropic universe with ordinary matter and gravity. The universe is far from exact homogeneity and isotropy at late times, and the effect of the non-linear structures has to be…

Astrophysics · Physics 2012-05-01 Syksy Rasanen

A primordial magnetic field may be generated during an inflationary period if conformal invariance is broken. We reexamine and generalize previous results about the magnetic field produced by couplings of the form $R^n…

Astrophysics · Physics 2009-10-28 F. D. Mazzitelli , F. M. Spedalieri

We give a pedagogical introduction to two aspects of magnetic fields in the early universe. We first focus on how to formulate electrodynamics in curved space time, defining appropriate magnetic and electric fields and writing Maxwell…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Kandaswamy Subramanian

Different mechanisms which may possibly explain existence of magnetic fields on astronomically large scales are described. A recently suggested model of magnetic fields generation slightly before hydrogen recombination is discussed in more…

Astrophysics · Physics 2007-05-23 A. D. Dolgov

We show that if the field seeding the formation of the cosmic structures is a dynamically arising bosonic condensate, the features we observe in the CMB might be interpreted as a manifestation of its compositeness.

General Relativity and Quantum Cosmology · Physics 2009-03-02 G. L. Alberghi

The amplification of magnetic fields plays an important role in explaining numerous astrophysical phenomena associated with binary neutron-star mergers, such as mass ejection and the powering of short gamma-ray bursts. Magnetic fields in…

High Energy Astrophysical Phenomena · Physics 2023-03-15 Michail Chabanov , Samuel D. Tootle , Elias R. Most , Luciano Rezzolla

We study the inflationary generation of helical cosmological magnetic fields in a higher-dimensional generalization of the electromagnetic theory. For this purpose, we also include a parity breaking piece to the electromagnetic action. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Kumar Atmjeet , T. R. Seshadri , Kandaswamy Subramanian

The intergalactic magnetic field within filaments should be less polluted by magnetised outflows from active galaxies than magnetic fields in clusters. Therefore, filaments may be a better laboratory to study magnetic field amplification by…

Astrophysics · Physics 2009-11-13 M. Bruggen , M. Ruszkowski , A. Simionescu , M. Hoeft , C. Dalla Vecchia
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