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Related papers: Magnetogenesis in bouncing cosmology

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We study the effect of variations of the electromagnetic coupling on the process of generation of primordial magnetic fields. We find that only through a significant growth of the electromagnetic coupling minimum seed fields can be…

Astrophysics · Physics 2009-03-24 O. Bertolami , R. Monteiro

Today, the generation of magnetic fields in solar-type stars and its relation to activity and rotation can coherently be explained, although it is certainly not understood in its entirety. Rotation facilitates the generation of magnetic…

Astrophysics · Physics 2009-11-13 A. Reiners , A. Scholz , J. Eislöffel , G. Hallinan , E. Berger , M. Browning , J. Irwin , M. Küker , S. Matt

I review some of the mechanisms through which primordial magnetic fields may be created in the electroweak phase transition. I show that no magnetic fields are produced initially from two-bubble collisions in a first-order transition. The…

High Energy Physics - Phenomenology · Physics 2016-10-26 Ola Tornkvist

We present new generation mechanisms of magnetic fields in supernova remnant shocks propagating to partially ionized plasmas in the early universe. Upstream plasmas are dissipated at the collisionless shock, but hydrogen atoms are not…

High Energy Astrophysical Phenomena · Physics 2022-09-08 Shuhei Kashiwamura , Yutaka Ohira

Increasing evidence suggests that cosmological sheets, filaments, and voids may be substantially magnetized today. The origin of magnetic fields in the intergalactic medium (IGM) is, however, currently uncertain. It seems well known that…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-27 Mathieu Langer , Jean-Baptiste Durrive

We consider the evolution of primordial magnetic fields generated during cosmological, electroweak or QCD, phase transitions. We assume that the magnetic field generation can be described as an injection of magnetic energy to cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-24 Tina Kahniashvili , Alexander G. Tevzadze , Axel Brandenburg , Andrii Neronov

We propose a mechanism for the early generation of the mean Intracluster magnetic field in terms of magnetized galactic winds. These winds are the result of starburst phases of the cluster galaxies, assumed to produce the predominant…

Astrophysics · Physics 2009-10-31 Heinrich J. Voelk , A. M. Atoyan

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

We explore the possibility of generating large-scale magnetic fields from second-order cosmological perturbations during the pre-recombination era. The key process for this is Thomson scattering between the photons and the charged particles…

Astrophysics · Physics 2009-06-23 Satoshi Maeda , Satoshi Kitagawa , Tsutomu Kobayashi , Tetsuya Shiromizu

In this thesis, we have studied the generation and evolution of the magnetic field in the early Universe. We investigated the generation of magnetic fields in the presence of chiral symmetry and gravitational anomaly. We have used modified…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-20 Arun Kumar Pandey

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

Large-scale coherent magnetic fields are observed in galaxies and clusters, but their ultimate origin remains a mystery. We reconsider the prospects for primordial magnetogenesis by a cosmic string network. We show that the magnetic flux…

Astrophysics · Physics 2008-11-26 Diana Battefeld , Thorsten Battefeld , Daniel H. Wesley , Mark Wyman

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

Cosmological hydrodynamical simulations of primordial star formation suggest that the gas within the first star-forming halos is turbulent. This has strong implications on the subsequent evolution, in particular on the generation of…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Sharanya Sur , Dominik R. G. Schleicher , Robi Banerjee , Christoph Federrath , Ralf S. Klessen

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

Astrophysics · Physics 2015-06-24 Yutaka Fujita , Tsunehiko N. Kato

The large-scale magnetic fields we observe today in galaxies and galaxy clusters could be the result of a pure quantum effect taking place during inflation, to wit, the creation of particles (photons) out from the vacuum in a curved…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-26 Leonardo Campanelli

We present results of a detailed and fully non-linear numerical and analytical investigation of magnetic field evolution from the very earliest cosmic epochs to the present. We find that, under reasonable assumptions concerning the…

Astrophysics · Physics 2009-11-07 Robi Banerjee , Karsten Jedamzik

It is well known that when two types of perturbations interact in cosmological perturbation theory, the interaction may lead to the generation of a third type. In this article we discuss the generation of magnetic fields from such…

General Relativity and Quantum Cosmology · Physics 2014-03-24 Bob Osano

A non-singular bouncing cosmology is generically obtained in loop quantum cosmology due to non-perturbative quantum gravity effects. A similar picture can be achieved in standard general relativity in the presence of a scalar field with a…

General Relativity and Quantum Cosmology · Physics 2014-03-17 Yi-Fu Cai , Edward Wilson-Ewing

The evolution of the gauge coupling is modelled using a scalar degree of freedom whose homogeneous and inhomogeneous modes evolve from an ordinary inflationary phase to the subsequent epochs. Depending upon various parameters (scalar mass,…

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