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It is shown that the evolution of the (Abelian) gauge coupling during an inflationary phase of de Sitter type drives the growth of the two-point function of the magnetic inhomogeneities. After examining the constraints on the variation of…

Astrophysics · Physics 2009-11-06 Massimo Giovannini

Large scale magnetic fields seem to be present in almost all astrophysical systems and scales from planets to superclusters of galaxies and in very low density intergalactic media. The upper limit of primordial magnetic fields (PMF) has…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-26 Anwar Saleh AlMuhammad

We propose a new self-consistent dynamo mechanism for the generation of large-scale magnetic fields in natural objects. Recent computational studies have described the formation of large-scale vortices (LSVs) in rotating turbulent…

Fluid Dynamics · Physics 2015-06-24 Celine Guervilly , David W. Hughes , Chris A. Jones

Recently, there are several reports that the cosmic magnetic fields on Mpc scale in void region is larger than $\sim 10^{-15}$G with an uncertainty of a few orders from the current blazar observations. On the other hand, in inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Tomohiro Fujita , Shuichiro Yokoyama

Einstein-Maxwell theory coupled to a dilaton is known to give rise to extremal solutions with hyperscaling violation. We study the behaviour of these solutions in the presence of a small magnetic field. We find that in a region of parameter…

High Energy Physics - Theory · Physics 2013-04-05 Nilay Kundu , Prithvi Narayan , Nilanjan Sircar , Sandip P. Trivedi

The origin of large scale cosmological magnetic fields remains a mystery, despite the continuous efforts devoted to that problem. We present a new model of magnetic field generation, based on local charge separation provided by an…

Astrophysics · Physics 2009-04-16 Mathieu Langer , Jean-Loup Puget , Nabila Aghanim

We analyse the evolution of primordial magnetic fields in spatially flat Friedmann universes and reconsider the belief that, after inflation, these fields decay adiabatically on all scales. Without~abandoning classical electromagnetism or…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-11 Christos G. Tsagas

It is shown that the standard cosmological model predicts {\it ab initio} generation of large-scale but very small-amplitude cosmic magnetic fields at the epoch of recombination of the primeval plasma. Matter velocities dominated by…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

There is an observational indication of extragalactic magnetic fields. No known astrophysical process can explain the origin of such large scale magnetic fields, which motivates us to look for their origin in primordial inflation. By…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Teruaki Suyama , Jun'ichi Yokoyama

Magnetic fluctuations generated by a tangling of the mean magnetic field by velocity fluctuations are studied in a developed turbulent convection with large magnetic Reynolds numbers. We show that the energy of magnetic fluctuations depends…

Astrophysics · Physics 2008-11-26 I. Rogachevskii , N. Kleeorin

We discuss an extended version of electromagnetism in which the usual gauge fixing term is promoted into a physical contribution that introduces a new scalar state in the theory. This new state can be generated from vacuum quantum…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Jose Beltrán Jiménez , Antonio L. Maroto

We investigate primordial magnetogenesis by assuming the gauge field is prepared in a thermal state during inflation rather than the standard Bunch-Davies vacuum. The temperature $\mathcal{T}$ introduces a physical scale that breaks…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-12 Arjun Berera , Suddhasattwa Brahma , Zizang Qiu , Rudnei O. Ramos

The primordial density fluctuation inevitably couples to all forms of matter via loop corrections and depends on the ambient conditions while inflation was ongoing. This gives us an opportunity to observe processes which were in progress…

Astrophysics · Physics 2009-08-24 David Seery

We study the backreaction problem in a mechanism of magnetogenesis from inflation. In usual analysis, it has been assumed that the backreaction due to electromagnetic fields spoils inflation once it becomes important. However, there exists…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-09 Sugumi Kanno , Jiro Soda , Masa-aki Watanabe

We investigate what can be said about the interaction of scalar fields with Abelian gauge fields during a quasi-de Sitter phase of expansion and under the assumption that the electric and the magnetic susceptibilities do not coincide. The…

High Energy Physics - Theory · Physics 2013-11-07 Massimo Giovannini

Inflation is known to produce both gravitational waves and seed magnetic fields on scales well beyond the size of the horizon. The general relativistic interaction between these two sources at the end of inflation showed a significant…

Astrophysics · Physics 2009-11-13 Christos G. Tsagas

Three-dimensional electron phase space holes are shown to be positive charges on the plasma background which produce a radial electric field and force the trapped electron component into an azimuthal drift. In this way electron holes…

Space Physics · Physics 2012-04-20 R. A. Treumann , W. Baumjohann

We describe a simple and efficient mechanism by which very heavy particles are copiously created from a primordial inflationary epoch. It works for scalar fields which are massless or very light during inflation and acquire a large mass…

High Energy Physics - Phenomenology · Physics 2010-04-05 G. F. Giudice , A. Riotto , A. Zaffaroni

It is shown that the electric current of massive fermions along the external magnetic field can be excited in the case when particles possess anomalous magnetic moments and electroweakly interact with background matter. This current is…

High Energy Physics - Phenomenology · Physics 2018-02-15 Maxim Dvornikov

A framework is introduced for coupling the evolution of galactic magnetic fields sustained by the mean-field dynamo with the formation and evolution of galaxies in cold dark matter cosmology. Estimates of the steady-state strength of the…

Astrophysics of Galaxies · Physics 2015-05-20 Luiz Felippe S. Rodrigues , Anvar Shukurov , Andrew Fletcher , Carlton Baugh
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