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We study the generation of primeval magnetic fields during inflation era in nonlinear theories of electrodynamics. Although the intensity of the produced fields strongly depends on characteristics of inflation and on the form of…

Astrophysics · Physics 2008-11-26 L. Campanelli , P. Cea , G. L. Fogli , L. Tedesco

We investigate the origin and evolution of primordial electric and magnetic fields in the early universe, when the expansion is governed by a cosmological constant $\Lambda_0$. Using the gravitoelectromagnetic inflationary formalism with…

General Relativity and Quantum Cosmology · Physics 2009-04-06 Federico Agustin Membiela , Mauricio Bellini

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

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

The most studied mechanism of inflationary magnetogenesis relies on the time-dependence of the coefficient of the gauge kinetic term $F_{\mu\nu}\,{F}^{\mu\nu}$. Unfortunately, only extremely finely tuned versions of the model can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Chiara Caprini , Lorenzo Sorbo

The origin of large scale magnetic fields is one of the most puzzling topics in cosmology and astrophysics. It is assumed that the observed magnetic fields result from the amplification of an initial field produced in the early universe. In…

General Relativity and Quantum Cosmology · Physics 2014-12-18 Hector J. Hortua , Leonardo Castañeda

We investigate the statistical properties of isotropic, stochastic, Gaussian distributed, helical magnetic fields characterized by different shapes of the energy spectra at large length scales and study the associated realizability…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-24 Axel Brandenburg , Ruth Durrer , Tina Kahniashvili , Sayan Mandal , Weichen Winston Yin

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 analyze the generation of seed magnetic fields during de Sitter inflation considering a non-invariant conformal term in the electromagnetic Lagrangian of the form $-\frac14 I(\phi) F_{\mu \nu} \widetilde{F}^{\mu \nu}$, where $I(\phi)$ is…

Astrophysics · Physics 2010-01-26 Leonardo Campanelli

The generation of large-scale magnetic fields in inflationary cosmology is explored, in particular, in a kind of moduli inflation motivated by racetrack inflation in the context of the Type IIB string theory. In this model, the conformal…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Kazuharu Bamba

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…

The hot plasma above the electroweak scale contains (hyper) charged scalar particles which are coupled to Abelian gauge fields. Scalars may interact with gravity in a non-conformally invariant way and thus their fluctuations can be…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Giovannini , M. Shaposhnikov

Generation of magnetic fields during inflation is a promising mechanism for the origin of the observed large scale magnetic fields in the universe. Among several attempts, a popular model is one where the inflaton and the electromagnetic…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-27 Ramkishor Sharma , Kandaswamy Subramanian , T. R. Seshadri

We consider the possibility of generation of the seeds of primordial magnetic field on inflation and show that the effect of the back reaction of this field can be very important. Assuming that back reaction does not spoil inflation we find…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-28 Vittoria Demozzi , Viatcheslav Mukhanov , Hector Rubinstein

The origin of large-scale magnetic field in the universe is one of the greatest mysteries in modern cosmology. We present a new mechanism for generation of large-scale magnetic field, based on the power-counting renormalizable theory of…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-07 Satoshi Maeda , Shinji Mukohyama , Tetsuya Shiromizu

We point out that a successful inflationary magnetogenesis could be realised if we break the local U(1) gauge symmetry during inflation. The effective electric charge is fixed as a fundamental constant, which allows us to obtain an almost…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-24 Guillem Domènech , Chunshan Lin , Misao Sasaki

Inflation has long been thought as the best way of producing primordial large-scale magnetic fields. To achieve fields strong enough to seed the galactic dynamo, most of the mechanisms operate outside conventional electromagnetic theory.…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-09 Christos G. Tsagas

There is strong observational evidence for the presence of large-scale magnetic fields MF in galaxies and clusters, with strength $\sim \mu$G and coherence lenght on the order of Kpc. However its origin remains as an outstanding problem.…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-08 Eduard F. Piratova , Edilson A. Reyes , Héctor J. Hortúa

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

A possible explanation for the origin of the magnetic fields observed today in matter structures is that they were generated in the primordial universe. After briefly revising the model of a primordial stochastic magnetic field and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Chiara Caprini