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The existence of large-scale magnetic fields in galaxies is well established, but there is no accepted mechanism for generating a primordial field which could grow into what is observed today. We discuss a model which attempts to account…

High Energy Physics - Phenomenology · Physics 2011-05-05 W. Daniel Garretson , George B. Field , Sean M. Carroll

Evidence repeatedly suggests that cosmological sheets, filaments and voids may be substantially magnetised today. The origin of magnetic fields in the intergalactic medium is however currently uncertain. We discuss a magnetogenesis…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-26 Mathieu Langer , Jean-Baptiste Durrive

The magnetic fields of spiral galaxies are so strong that they cannot be primordial. Their typical values are over one billion times higher than any value predicted for the early Universe. Explaining this immense growth and incorporating it…

Astrophysics of Galaxies · Physics 2020-09-30 Evangelia Ntormousi , Konstantinos Tassis , Fabio Del Sordo , Francesca Fragkoudi , Rüdiger Pakmor

While the presence of magnetic fields on low-mass stars is attributed to a dynamo process essentially driven by convective motions, the existence of magnetic fields on intermediate-mass stars has very likely other reasons. Presuming that…

Solar and Stellar Astrophysics · Physics 2013-09-30 Rainer Arlt

We study the evolution of primordial magnetic fields in an expanding cosmic plasma. For this purpose we present a comprehensive theoretical model to consider the evolution of MHD turbulence that can be used over a wide range of physical…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Tina Kahniashvili , Axel Brandenburg , Alexander G. Tevzadze

Magnetic fields correlated on several kiloparsec scales are seen in spiral galaxies. Their origin could be due to the winding up of a primordial cosmological field or due to amplification of a small seed field by a turbulent galactic…

Astrophysics · Physics 2007-05-23 K. Subramanian

Large scale magnetic fields represent a triple point where cosmology, high-energy physics and astrophysics meet for different but related purposes. After reviewing the implications of large scale magnetic fields in these different areas,…

High Energy Physics - Phenomenology · Physics 2007-05-23 Massimo Giovannini

The galactic magnetic field is commonly supposed to be due to a dynamo acting on some large scale seed field. A major difficulty with this idea is that estimates of reasonable seed field strengths tend to be quite low, on the order of…

Astrophysics · Physics 2007-05-23 Ethan T. Vishniac

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 show that coherent magnetic field is generated spontaneously when a large domain wall is created in the early universe. It is caused by two dimensional massless fermions bounded to the domain wall soliton. We point out that the magnetic…

High Energy Physics - Phenomenology · Physics 2009-10-28 Aiichi Iwazaki

The possible existence of a primordial magnetic field in the universe has been previously investigated in many articles. Studies involving the influence of a magnetic field in the nucleosyntesis era, studies considering the effects in the…

Astrophysics · Physics 2009-10-30 J. C. N. de Araujo , R. Opher

It is argued that large scale cosmic magnetic field could be generated in the primeval plasma slightly before hydrogen recombination. Non-zero vorticity, necessary for that, might be created by the photon diffusion in the second order in…

Astrophysics · Physics 2016-08-30 Z. Berezhiani , A. D. Dolgov

Observations of stable mainly dipolar magnetic fields at the surface of ~7% of single hot stars indicate that these fields are of fossil origin, i.e. they descend from the seed field in the molecular clouds from which the stars were formed.…

Solar and Stellar Astrophysics · Physics 2015-02-03 C. Neiner , S. Mathis , E. Alecian , C. Emeriau , J. Grunhut , the BinaMIcS , MiMeS collaborations

Non-abelian gauge theories may have a ferromagnet-like vacuum with a non-zero magnetic field, which also exists at finite temperature. We argue that the formation of the ferromagnet-like vacuum at GUT scales gives rise to a Maxwell magnetic…

High Energy Physics - Phenomenology · Physics 2010-11-30 Kari Enqvist , Poul Olesen

We review our current understanding of galactic dynamo theory, paying particular attention to numerical simulations both of the mean-field equations and the original three-dimensional equations relevant to describing the magnetic field…

Astrophysics of Galaxies · Physics 2014-12-12 Axel Brandenburg

A new mechanism for the evolution of primordial magnetic fields is described and analysed. The field evolution is followed from the time of its creation until the epoch of structure and galaxy formation. The mechanism takes into account the…

Astrophysics · Physics 2009-10-28 K. Dimopoulos , A. C. Davis

It is assumed that long range coherent magnetic fields in the universe were spontaneously generated at high temperature due to vacuum polarization of non-Abelian gauge fields, and resulted in the present intergalaxy magnetic field. The zero…

High Energy Physics - Phenomenology · Physics 2011-06-27 E. Elizalde , V. Skalozub

Primordial magnetic fields (PMFs) are magnetic fields generated during the early universe. These fields are thought to be the seeds of extragalactic magnetic fields. The origin of PMFs is not well known. Further, if they are indeed sources…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Ganga R. Nair , V. Sreenath

$\gamma$-ray emission of blazars infer the presence of large-scale magnetic fields in the intergalactic medium, but their origin remains a mystery. Using recent data from MAGIC, H.E.S.S. and $\textit{Fermi}$-LAT, we investigate whether the…

High Energy Physics - Phenomenology · Physics 2024-05-07 María Olalla Olea-Romacho

In this paper we show that noncommutativity in spatial coordinates can generate magnetic field in the early Universe on a horizon scale. The strength of such a magnetic field depends on the number density of massive charged particles…

High Energy Physics - Phenomenology · Physics 2009-10-07 Anupam Mazumdar , Mohammad M. Sheikh-Jabbari