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We propose a mechanism for the generation of magnetic fields on cosmological scales that is operative after recombination. An essential ingredient is an instability (of parametric resonance type) of the electromagnetic field driven by an…

High Energy Physics - Phenomenology · Physics 2025-02-27 Robert Brandenberger , Jürg Fröhlich , Hao Jiao

The extraordinary energetic activity of magnetars is usually explained in terms of dissipation of a huge internal magnetic field of the order of $10^{15-16}$G. How such a strong magnetic field can originate during the formation of a neutron…

High Energy Astrophysical Phenomena · Physics 2017-07-26 A. G. Pili , N. Bucciantini , L. Del Zanna

We study the linear magneto-hydrodynamical behaviour of a Newtonian cosmology with a viscous magnetized fluid of finite conductivity and generalise the Jeans instability criterion. The presence of the field favors the anisotropic collapse…

Astrophysics · Physics 2009-11-13 L. Vlahos , C. G. Tsagas , D. Papadopoulos

The origin of the magnetic field in galaxies is an open question in astrophysics. Several mechanisms have been proposed related, in general, with the generation of small seed fields amplified by a dynamo mechanism. In general, these…

Astrophysics · Physics 2009-10-30 O. D. Miranda , M. Opher , R. Opher

It was recently demonstrated that the evolution of helical magnetic field in the primordial plasma at temperatures $T\gtrsim10$ MeV is affected by the phenomenon of chiral quantum anomaly in the electroweak model, leading to a possibility…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-19 Oleksandr Tomalak , Yuri Shtanov

The main issue of the pulsar magnetosphere is how the rotation power is converted into both particle beams which causes pulsed emissions, and a highly relativistic wind of electron-positron plasmas which forms surrounding nebulae shining in…

High Energy Astrophysical Phenomena · Physics 2015-05-30 Tomohide Wada , Shinpei Shibata

Weak magnetic fields must have existed in the early Universe, as they were sourced by the cross product of electron density and temperature gradients through the Biermann-battery mechanism. In this paper we calculate the magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-15 Nanoom Lee , Yacine Ali-Haimoud

The mechanisms that generate "seed" magnetic fields in our Universe and that amplify them throughout cosmic time remain poorly understood. By means of fully-kinetic particle-in-cell simulations of turbulent, initially unmagnetized plasmas,…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-09 L. Sironi , L. Comisso , R. Golant

Magnetic fields are everywhere in nature and they play an important role in every astronomical environment which involves the formation of plasma and currents. It is natural therefore to suppose that magnetic fields could be present in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-22 Dai G. Yamazaki , Kiyotomo Ichiki , Toshitaka Kajino , Grant J. Mathew

Context. The influence of magnetic fields on stellar core collapse and explosion is not well explored. It depends on the possibility to amplify the pre-collapse fields. Without rotation this can happen by compression, convection, the…

Solar and Stellar Astrophysics · Physics 2015-03-17 Martin Obergaulinger , Hans-Thomas Janka

We derive a new model for neutrino-plasma interactions in an expanding universe that incorporates the collective effects of the neutrinos on the plasma constituents. We start from the kinetic description of a multi-species plasma in the…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 L. M. Perrone , G. Gregori , B. Reville , L. O. Silva , R. Bingham

We show that the evolution of magnetic fields in a primordial plasma, filled with Standard Model particles, at temperatures T > 10 MeV is strongly affected by the quantum chiral anomaly -- an effect that has been neglected previously.…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-19 Alexey Boyarsky , Juerg Froehlich , Oleg Ruchayskiy

The effective interaction of a neutrino with a photon in magnetized plasma is obtained from a strong field expansion in the electroweak standard model. The interaction is expressed by a Chern-Simons form of the neutrino current and the…

High Energy Physics - Phenomenology · Physics 2024-05-07 Kenzo Ishikawa , Yutaka Tobita

The properties of nuclear matter in the presence of a strong magnetic field, including the density-dependent symmetry energy, the chemical composition and spin polarizations, are investigated in the framework of the relativistic mean field…

Nuclear Theory · Physics 2013-01-18 Jianmin Dong , Umberto Lombardo , Wei Zuo , Hongfei Zhang

Primordial magnetic fields and massive neutrinos can leave an interesting signal in the CMB temperature and polarization. We perform a systematic analysis of general perturbations in the radiation-dominated universe, accounting for any…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 J. Richard Shaw , Antony Lewis

There are at present more then 30 theories about the origin of cosmic magnetic fields at galactic and intergalactic scales. Most of them rely on concepts of elementary particle physics, like phase transitions in the early Universe, string…

Astrophysics · Physics 2007-05-23 E. Battaner , H. Lesch

We study the amplification of magnetic fields in the collapse and the post-bounce evolution of the core of a non-rotating star of 15 solar masses in axisymmetry. To this end, we solve the coupled equations of magnetohydrodynamics and…

Solar and Stellar Astrophysics · Physics 2015-06-19 Martin Obergaulinger , Thomas Janka , Miguel Ángel Aloy Torás

We investigate the effects of a magnetic field on the thermodynamics of a neutron system at finite density and temperature. Our main motivation is to deepen the understanding of the physics of a class of neutron stars known as magnetars,…

Nuclear Theory · Physics 2019-06-12 E. J. Ferrer , A. Hackebill

Magnetars can accelerate cosmic rays to high energies through the unipolar effect, and are also copious soft photon emitters. We show that young, fast-rotating magnetars whose spin and magnetic moment point in opposite directions emit high…

Astrophysics · Physics 2009-11-07 Bing Zhang , Z. G. Dai , P. Meszaros , E. Waxman , A. K. Harding

The origin of galactic and extra-galactic magnetic fields is an unsolved problem in modern cosmology. A possible scenario comes from the idea of these fields emerged from a small field, a seed, which was produced in the early universe…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-14 Hector J. Hortua , Leonardo Castaneda , Juan M. Tejeiro
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