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We study the evolution of an inflation-generated magnetic field, due to its coupling to fluid motions, during cosmological phase transitions. We find that the magnetic field stays almost unchanged on large scales, while on small scales the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Tina Kahniashvili , Axel Brandenburg , Leonardo Campanelli , Bharat Ratra , Alexander G. Tevzadze

In this paper, we study the generation of a large scale magnetic field with amplitude of order $\mu$G in an inflationary model which has been introduced in hep-th/0310221. This inflationary model based on existence of a speed limit for…

High Energy Physics - Theory · Physics 2009-11-11 Mohammad A. Ganjali

Among primordial magnetogenesis models, inflation is a prime candidate to explain the current existence of cosmological magnetic fields. Assuming conformal invariance to be restored after inflation, their energy density decreases as…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-11 Vittoria Demozzi , Christophe Ringeval

If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field---e.g. the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Robert R. Caldwell , Leonardo Motta , Marc Kamionkowski

Spontaneous breaking of Lorentz invariance compatible with observational limits may realistically take place in the context of string theories, possibly endowing the photon with a mass. In this process the conformal symmetry of the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 O. Bertolami , D. F. Mota

The detection of magnetic fields at high redshifts, and in empty intergalactic space, support the idea that cosmic magnetism has a primordial origin. Assuming that Maxwellian electromagnetism and general relativity hold, and without…

General Relativity and Quantum Cosmology · Physics 2015-06-11 J. D. Barrow , C. G. Tsagas , K. Yamamoto

We study the backreaction problem in a mechanism of magnetogenesis from inflation. In usual analysis, it has been assumed that the backreaction due to electromagnetic fields spoils inflation once it becomes important. However, there exists…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-09 Sugumi Kanno , Jiro Soda , Masa-aki Watanabe

The universe is magnetized on all scales probed so far. On the largest scales, galaxies and galaxy clusters host magnetic fields at the micro Gauss level coherent on scales up to ten kpc. Recent observational evidence suggests that even the…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-26 Kandaswamy Subramanian

The inflationary production of magnetic field seeds for galaxies is discussed. The analysis is carried out by writing the wave equation of the electromagnetic field in curved spacetimes. The conformal invariance is broken by taking into…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. Lambiase , A. R. Prasanna

We discuss some aspects of Pereira et al. (2018) concerning magnetars described by nonlinear theories of the electromagnetism and make the case for the Born-Infeld Lagrangian. We focus on the increase of toroidal magnetic fields in these…

High Energy Astrophysical Phenomena · Physics 2019-04-12 Jonas P. Pereira , Jaziel G. Coelho , Rafael C. R. de Lima

The magnetogenesis scenarios triggered by the early variation of the gauge coupling are critically analyzed. In the absence of sources, it is shown that the electric and magnetic power spectra can be explicitly computed by means of…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-29 Massimo Giovannini

Large-scale magnetogenesis is analyzed within the Palatini approach when the gravitational action is supplemented by a contribution that is nonlinear in the Einstein-Hilbert term. While the addition of the nonlinear terms does not affect…

High Energy Physics - Theory · Physics 2021-12-08 Massimo Giovannini

There is a reformulation of magnetohydrodynamics in which the fundamental dynamical quantities are the positions and velocities of the lines of magnetic flux in the plasma, which turn out to obey equations of motion very much like ideal…

Astrophysics · Physics 2009-10-31 Mattias Christensson , Mark Hindmarsh

The Abelian Born-Infeld classical non-linear electrodynamic has been used to investigate the electric and magnetostatic fields generated by a point-like electrical charge at rest in an inertial frame. The results show a rich internal…

High Energy Physics - Theory · Physics 2008-11-26 S. O. Vellozo , Jose A. Helayel-Neto , A. W. Smith , L. P. G. De Assis

We show that the first structures that form in the universe should spontaneously generate magnetic fields. No primordial seed field is required for this "first dynamo". Although the first dynamo starts with kinetic plasma instabilities, we…

Cosmology and Nongalactic Astrophysics · Physics 2009-05-08 Andrei Gruzinov

In this paper I examine cosmological models that contain a stochastic background of nonlinear electromagnetic radiation. I show that for Born-Infeld electrodynamics the equation of state parameter, $w=P/\rho$, remains close to 1/3…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Dan N. Vollick

We study limits on a primordial magnetic field arising from cosmological data, including that from big bang nucleosynthesis, cosmic microwave background polarization plane Faraday rotation limits, and large-scale structure formation. We…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-27 Tina Kahniashvili , Alexander G. Tevzadze , Shiv K. Sethi , Kanhaiya Pandey , Bharat Ratra

In the standard model there are charges with abelian anomaly only (e.g. right-handed electron number) which are effectively conserved in the early universe until some time shortly before the electroweak scale. A state at finite chemical…

Astrophysics · Physics 2009-10-30 M. Joyce , M. Shaposhnikov

This review concerns the origin and the possible effects of magnetic fields in the early Universe. We start by providing to the reader with a short overview of the current state of art of observations of cosmic magnetic fields. We then…

Astrophysics · Physics 2009-07-09 Dario Grasso , H. R. Rubinstein

We present preliminary results on the possible effects that primordial magnetic fields can have for a warm inflation scenario, based on global supersymmetry, with a new-inflation-type potential. This work is motivated by two considerations:…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Gabriella Piccinelli , Angel Sanchez , Alejandro Ayala , Ana Julia Mizher
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