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The generation of magnetic fields by a battery, operating in an ion-electron plasma around a Kerr black hole, is studied in the 3+1 split of the Kerr metric. It is found that the gravitomagnetic contributions to the electron partial…

Astrophysics · Physics 2015-06-24 Ramon Khanna

We study the generation and evolution of density perturbations and peculiar velocities due to primordial magnetic fields. We assume that a random magnetic field was present before recombination and follow the field's effect on the baryon…

Astrophysics · Physics 2009-10-22 Eun-jin Kim , Angela Olinto , Robert Rosner

We review current ideas on the origin of galactic and extragalactic magnetic fields. We begin by summarizing observations of magnetic fields at cosmological redshifts and on cosmological scales. These observations translate into constraints…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lawrence M. Widrow , Dongsu Ryu , Dominik Schleicher , Kandaswamy Subramanian , Christos G. Tsagas , Rudolf A. Treumann

Recent gamma-ray observations of TeV blazars exhibits the deficits of the secondary GeV cascade photons. This suggests the existence of the intergalactic magnetic fields, which may have a primordial origin. One of the mechanisms that can…

High Energy Physics - Phenomenology · Physics 2018-11-16 Kohei Kamada

In the present work, we have studied the spectrum of the primordial gravitational waves due to magnetic instability in the presence of neutrino asymmetry. The magnetic instability generates a helical magnetic field on a large scale. The…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-23 Arun Kumar Pandey , Pravin Kumar Natwariya , Jitesh R Bhatt

We consider the dynamics of electromagnetic fields in an almost-Friedmann-Robertson-Walker universe using the covariant and gauge-invariant approach of Ellis and Bruni. Focusing on the situation where deviations from the background model…

General Relativity and Quantum Cosmology · Physics 2009-12-30 Mattias Marklund , Peter K. S. Dunsby , Gert Brodin

We use the cosmic microwave background temperature anisotropy to place limits on large-scale magnetic fields in an inhomogeneous (perturbed Friedmann) universe. If no assumptions are made about the spacetime geometry, only a weak limit can…

Astrophysics · Physics 2017-08-23 C. A. Clarkson , A. A. Coley , R. Maartens , C. G. Tsagas

In the framework of mixed Higgs-Starobinsky inflation, we consider the generation of Abelian gauge fields due to their nonminimal coupling to gravity (in two different formulations of gravity -- metric and Palatini). We couple the…

General Relativity and Quantum Cosmology · Physics 2022-12-29 R. Durrer , O. Sobol , S. Vilchinskii

We demonstrate that the Biermann battery mechanism for the creation of large scale magnetic fields can arise in a simple model protogalaxy. Analytic calculations and numerical simulations follow explicitly the generation of vorticity (and…

Astrophysics · Physics 2007-05-23 George Davies , Lawrence M. Widrow

We extend some previous attempts to explain the origin and evolution of primordial magnetic fields during inflation induced from a 5D vacuum. We show that the usual quantum fluctuations of a generalized 5D electromagnetic field cannot…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Federico Agustín Membiela , Mauricio Bellini

In view of several conflicting results, we reanalyze the effects of magnetic fields on the primordial nucleosynthesis. In the case the magnetic field is homogeneous over a horizon volume, we show that the main effects of the magnetic field…

Astrophysics · Physics 2008-11-26 D. Grasso , H. R. Rubinstein

Magnetic fields large enough to be observable are ubiquitous in astrophysics, even at extremely large length scales. This has led to the suggestion that such fields are seeded at very early (inflationary) times, and subsequently amplified…

High Energy Physics - Theory · Physics 2015-05-20 Brett McInnes

For finite systems boundaries can introduce remarkable novel features. A well known example is the Casimir effect [1, 2] that is observed in quantum electrodynamic systems. In classical systems too novel effects associated with finite…

Primordial magnetic fields possibly generated in the very early universe are one of the candidates for the origin of magnetic fields observed in many galaxies and galaxy clusters. After recombination, the dissipation process of the…

Astrophysics · Physics 2009-11-11 Hiroyuki Tashiro , Naoshi Sugiyama

Problems and perspectives concerning the existence of large-scale magnetic fields are described. Heeding observations, possible origins and implications of magnetic fields in spiral galaxies and in regular clusters are scrutinized in…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Giovannini

We study the generation of magnetic field in Higgs-inflation models where the Standard Model Higgs boson has a large coupling to the Ricci scalar. We couple the Higgs field to the Electromagnetic fields via a non- renormalizable dimension…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Moumita Das , Subhendra Mohanty

A stochastic magnetic field in the early Universe will produce anisotropies in the temperature and polarization of the cosmic microwave background. We derive analytic expressions for the microwave background temperature and polarization…

Astrophysics · Physics 2008-11-26 Andrew Mack , Tina Kahniashvili , Arthur Kosowsky

Earlier Enqvist and Olesen have shown that formation of ferromagnetic planar walls in vacuum at GUT scales in comoving plasmas may generate a large scale magnetic field of $B_{now}\simeq{10^{-14}G}$. In this paper we show that starting from…

General Relativity and Quantum Cosmology · Physics 2015-06-18 L. C. Garcia de Andrade

Nonlinear dynamics creates vortical currents when the tight-coupling approximation between photons and baryons breaks down around the time of recombination. This generates a magnetic field at second order in cosmological perturbations,…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-28 Elisa Fenu , Cyril Pitrou , Roy Maartens

We propose that strong magnetic fields should be generated at shock waves associated with formation of galaxies or clusters of galaxies by the Weibel instability, an instability in collisionless plasmas. The strength of the magnetic fields…

Astrophysics · Physics 2009-11-13 Yutaka Fujita , Tsunehiko N. Kato
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