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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

Magnetic fields are generated in ionized objects rotating with respect to a radiation background. Based on conservation of canonical ion momentum, it has been previously suggested that even if the radiation intensity is unrestricted the…

Astrophysics · Physics 2009-11-10 L. Chuzhoy

The origin and maintenance of coherent magnetic fields in the Universe is reviewed with an emphasis on the possible challenges that arise in their theoretical understanding. We begin with the interesting possibility that magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-12 Kandaswamy Subramanian

We consider that no mean magnetic field exists during this epoch, but that there is a mean magnetic energy associated with large-scale magnetic inhomogeneities. We study the evolution of these inhomogeneities and their influence on the…

Astrophysics · Physics 2009-01-14 E. Battaner , E. Florido , J. Jimenez-Vicente

The dynamics of a binary neutron stars merger is governed by physics under the most extreme conditions, including strong spacetime curvature, ultra-high matter densities, luminous neutrino emission and the rapid amplification of the initial…

High Energy Astrophysical Phenomena · Physics 2025-09-17 Ricard Aguilera-Miret , Jan-Erik Christian , Stephan Rosswog , Carlos Palenzuela

We discuss generation of magnetic field from cosmological perturbations. We consider the evolution of three component plasma (electron, proton and photon) evaluating the collision term between elecrons and photons up to the second order.…

Detailed physical processes of magnetic field generation from density fluctuations in the pre-recombination era are studied. Solving Maxwell equations and the generalized Ohm's law, the evolutions of the net charge density, the electric…

Astrophysics · Physics 2008-11-26 Keitaro Takahashi , Kiyotomo Ichiki , Naoshi Sugiyama

Gravitational wave production induces a strong constraint on the amplitude of a primordial magnetic field. It has been shown that the nucleosynthesis bound for a stochastic gravitational wave background implies that causally generated…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 Chiara Caprini , Ruth Durrer , Elisa Fenu

The coupling between a primordial magnetic field and the cosmic axion field generates a helical component of the magnetic field around the time in which the axion starts to oscillate. If the energy density of the seed magnetic field is…

Astrophysics · Physics 2008-11-26 L. Campanelli , M. Giannotti

Here we summarize our recent results of high-resolution computer simulations on the turbulent amplification of weak magnetic seed fields showing that such fields will be exponentially amplified also during the gravitational collapse…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-22 Robi Banerjee , Sharanya Sur , Christoph Federrath , Dominik R. G. Schleicher , Ralf S. Klessen

Magnetized high energy density physics offers new opportunities for observing magnetic field-related physics for the first time in the laser-plasma context. We focus on one such phenomenon, which is the ability of a laser-irradiated…

Plasma Physics · Physics 2020-08-26 Y. Shi , K. Weichman , R. J. Kingham , A. V. Arefiev

The origin and structure of the magnetic fields in the interstellar medium of spiral galaxies is investigated with 3D, non-ideal, compressible MHD simulations, including stratification in the galactic gravity field, differential rotation…

Astrophysics of Galaxies · Physics 2013-04-01 F. A. Gent , A. Shukurov , A. Fletcher , G. R. Sarson , M. J. Mantere

In this work we consider the most general electromagnetic theory in curved space-time leading to linear second order differential equations, including non-minimal couplings to the space-time curvature. We assume the presence of a temporal…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Jose Beltran Jimenez , Antonio L. Maroto

Recently the lower bounds of the intergalactic magnetic fields $10^{-16} \sim 10^{-20}$ Gauss are set by gamma-ray observations while it is unlikely to generate such large scale magnetic fields through astrophysical processes. It is known…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-17 Shohei Saga , Maresuke Shiraishi , Kiyotomo Ichiki , Naoshi Sugiyama

Primordial magnetic fields could explain the large-scale magnetic fields present in the Universe. Inflation and phase transitions in the early Universe could give rise to such fields with unique characteristics. We investigate the…

Magnetic fields in galaxies are believed to be the result of dynamo amplification of initially weak seed fields, reaching equipartition strength inside the interstellar medium. The small-scale dynamo appears to be a viable mechanism to…

Astrophysics of Galaxies · Physics 2017-08-16 Michael Rieder , Romain Teyssier

A linear but global numerical model for the magnetorotational instability (MRI) in disk geometry is considered to estimate the instability parameters for galaxies. Similarity rules suggested by a local analysis are applied to reveal a…

Astrophysics · Physics 2016-08-16 L. L. Kitchatinov , G. Rüdiger

Large-scale magnetic fields are observed today to be coherent on galactic scales. While there exists an explanation for their amplification and their specific configuration in spiral galaxies -- the dynamo mechanism -- a satisfying…

High Energy Physics - Theory · Physics 2009-12-04 Rhiannon Gwyn , Stephon Alexander , Robert H. Brandenberger , Keshav Dasgupta

The property of the spectrum of large-scale magnetic fields generated due to the breaking of the conformal invariance of the Maxwell theory through some mechanism in inflationary cosmology is studied. It is shown that the spectrum of the…

Astrophysics · Physics 2008-11-26 Kazuharu Bamba

The origin of magnetic fields in clusters of galaxies is still a matter of debate. Observations for intracluster magnetic fields over a wide range of redshifts are crucial to constrain possible scenarios for the origin and evolution of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-23 J. Xu , J. L. Han
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