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Related papers: Large-scale magnetic fields from inflation in dila…

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We investigate the generation of large scale magnetic fields in the universe from quantum fluctuations produced in the inflationary stage. By coupling these quantum fluctuations to the dilaton field and Ricci scalar, we show that the…

Astrophysics · Physics 2008-11-26 A. Akhtari Zavareh , A. Hojjati , B. Mirza

The generation of large-scale magnetic fields is studied in inflationary cosmology. We consider the violation of the conformal invariance of the Maxwell field by dilatonic as well as non-minimal gravitational couplings. We derive a general…

Astrophysics · Physics 2009-11-11 Kazuharu Bamba , Misao Sasaki

The generation of large-scale magnetic fields is studied in dilaton electromagnetism in noncommutative inflationary cosmology taking into account the effects of the spacetime uncertainty principle motivated by string theory. We show that it…

High Energy Physics - Phenomenology · Physics 2009-11-10 Kazuharu Bamba , J. Yokoyama

Generation of large-scale magnetic fields is studied in dilaton electromagnetism in noncommutative inflationary cosmology, taking into account the effects of the spacetime uncertainty principle motivated by string theory. We show that it is…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kazuharu Bamba , J. Yokoyama

The interrelation between the generation of large-scale electric fields and that of large-scale magnetic fields due to the breaking of the conformal invariance of the electromagnetic field in inflationary cosmology is studied. It is shown…

Astrophysics · Physics 2009-06-23 Kazuharu Bamba

Generation of large-scale magnetic fields in inflationary cosmology is studied in teleparallelism, where instead of the scalar curvature in general relativity, the torsion scalar describes the gravity theory. In particular, we investigate a…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 Kazuharu Bamba , Chao-Qiang Geng , Ling-Wei Luo

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

We explore the generation of large-scale magnetic fields from inflation in teleparallelism, in which the gravitational theory is described by the torsion scalar instead of the scalar curvature in general relativity. In particular, we…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-02 Kazuharu Bamba , Chao-Qiang Geng , Ling-Wei Luo

The generation of primordial magnetic seed fields during inflation is studied in a theory derived from the one-loop vacuum polarization effective action of the photon in a curved background. This includes terms which couple the curvature to…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Kerstin E. Kunze

In most of the literature on evolution of cosmological magnetic fields, it is found that large-scale magnetic fields evolve as $B^{2}\propto a^{-4}$ (adiabatic magnetic decay) where $a$ is the cosmological scale factor and $B$ is the…

General Relativity and Quantum Cosmology · Physics 2020-04-23 Timothy Oreta , Bob Osano

We discuss the generation of large-scale magnetic fields due to the breaking of the conformal invariance in the electromagnetic field through the $CPT$-even dimension-six Chern-Simons-like effective interaction with a fermion current in…

Astrophysics · Physics 2008-12-18 K. Bamba , C. Q. Geng , S. H. Ho

We consider the possibility of inflationary magnetogenesis due to dynamical couplings of the electromagnetic fields to gravity. We find that large primordial magnetic fields can be generated during inflation without the strong coupling…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-26 Peng Qian , Zong-Kuan Guo

We explore the generation of large-scale magnetic fields in the so-called moduli inflation. The hypercharge electromagnetic fields couple to not only a scalar field but also a pseudoscalar one, so that the conformal invariance of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-30 Kazuharu Bamba

We consider the generation of large-scale magnetic fields in slow-roll inflation. The inflaton field is described in a supergravity framework where the conformal invariance of the electromagnetic field is generically and naturally broken.…

Astrophysics · Physics 2009-06-23 Jerome Martin , Jun'ichi Yokoyama

In this paper, we study the generation of a large scale magnetic field with amplitude of order $\mu$G in an inflationary model which has been introduced in hep-th/0310221. This inflationary model based on existence of a speed limit for…

High Energy Physics - Theory · Physics 2009-11-11 Mohammad A. Ganjali

We estimate the strength of large-scale magnetic fields produced during inflation in the framework of Dirac-Born-Infeld (DBI) theories. This analysis is sufficiently general in the sense that it covers most of conformal symmetry breaking…

Astrophysics · Physics 2010-05-12 Kazuharu Bamba , Nobuyoshi Ohta , Shinji Tsujikawa

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

We calculate, in the free Maxwell theory, the renormalized quantum vacuum expectation value of the two-point magnetic correlation function in de Sitter inflation. We find that quantum magnetic fluctuations remain constant during inflation…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-28 Leonardo Campanelli

If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field---e.g. the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Robert R. Caldwell , Leonardo Motta , Marc Kamionkowski

Primordial magnetic fields of cosmologically interesting field strengths can be generated from gravitationally coupled electrodynamics during inflation. As the cosmological constraints require this to be power law inflation it is not…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-14 Kerstin E. Kunze
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