English
Related papers

Related papers: On Primordial Magnetic Fields

200 papers

The ingredients required to create a magnetic field in the early Universe are identified, and compared with Sakharov's conditions for baryogenesis. It is also shown that a long range coherent magnetic field is not generated by the classical…

Astrophysics · Physics 2009-10-28 Sacha Davidson

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

In this contribution we will shortly review the main mechanism through which primordial magnetic fields may affect the electroweak baryogenesis. It is shown that although strong magnetic fields might enhance the strength of the electroweak…

High Energy Physics - Phenomenology · Physics 2016-11-03 Dario Grasso

Magnetic fields are considered to be key components of massive stars, with a far-reaching impact on their evolution and ultimate fate. A magnetic mechanism was suggested for the collimated explosion of massive stars, relevant for…

Solar and Stellar Astrophysics · Physics 2024-10-28 Swetlana Hubrig , Markus Schöller , Silva P. Järvinen , Aleksandar Cikota , Michael Abdul-Masih , Ana Escorza , Ilya Ilyin

Massive stars are crucial building blocks of galaxies and the universe, as production sites of heavy elements and as stirring agents and energy providers through stellar winds and supernovae. The field of magnetic massive stars has seen…

Solar and Stellar Astrophysics · Physics 2015-05-27 Rolf Walder , Doris Folini , Georges Meynet

Most of the visible matter in the Universe is in a plasma state, or more specifically is composed of ionized or partially ionized gas permeated by magnetic fields. Thanks to recent advances on the theory and detection of cosmic magnetic…

Astrophysics · Physics 2009-11-11 E. M. de Gouveia Dal Pino

In this paper we show that the Universe is already strongly magnetized at very early epochs during cosmic evolution. Our calculations are based on the efficient amplification of weak magnetic seed fields, which are unavoidably present in…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Jacques M. Wagstaff , Robi Banerjee , Dominik Schleicher , Guenter Sigl

We propose a primordial-origin model for the composite configurations of global magnetic fields in spiral galaxies. We show that uniform tilted magnetic field wound up into a rotating disk galaxy can evolve into composite magnetic…

Astrophysics of Galaxies · Physics 2015-05-19 Yoshiaki Sofue , Mami Machida , Takahiro Kudoh

A generation of magnetic fields from cosmological density perturbations is investigated. In the primordial plasma before cosmological recombination, all of the materials except dark matter in the universe exist in the form of photons,…

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

It has been argued that electroweak baryogenesis generates a left-handed primordial magnetic field. The helicity density of the primordial magnetic field today is estimated to be $\sim 10^2 n_b$ where $n_b\sim 10^{-6}$ /cm$^3$ is the…

Astrophysics · Physics 2007-05-23 Tanmay Vachaspati

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

Dynamical extra dimensions break the conformal invariance of Maxwell's equations in four dimensions. A higher dimensional background with $n$ contracting extra dimensions and four expanding dimensions is matched to an effectively four…

High Energy Physics - Phenomenology · Physics 2010-04-05 Kerstin E. Kunze

Yukawa interactions can mediate relatively long-range attractive forces between fermions in the early universe. Such a globally attractive interaction creates an instability that can result in the growth of structure in the affected species…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-18 Ruth Durrer , Alexander Kusenko

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

We constrain a primordial magnetic field (PMF) generated during a phase transition (PT) using the big bang nucleosynthesis bound on the relativistic energy density. The amplitude of the PMF at large scales is determined by the shape of the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-04 Tina Kahniashvili , Alexander G. Tevzadze , Bharat Ratra

In this Letter we reanalyse the question of the origin of magnetic fields during the electroweak phase transition. We show that their formation is intimately connected to some semiclassical configurations of the gauge fields, such as…

High Energy Physics - Phenomenology · Physics 2009-10-30 Dario Grasso , Antonio Riotto

Galactic magnetic fields are observed of order $\sim 10^{-6}G$, but their origin is not definitely known yet. In this paper we consider the primordial magnetic fields generated in the early universe and analyse their effects on the density…

Astrophysics · Physics 2016-08-30 Seoktae Koh , Chul H. Lee

We recently predicted the existence of random primordial magnetic fields (RPMF) in the form of randomly oriented cells with dipole-like structure with a cell size $L_0$ and an average magnetic field $B_0$. Here we investigate models for…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-24 Rafael S. de Souza , Luiz Felippe S. Rodrigues , Reuven Opher

The origin and growth of magnetic fields in galaxies is still something of an enigma. It is generally assumed that seed fields are amplified over time through the dynamo effect, but there are few constraints on the timescale. It has…