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We consider the amplification of electromagnetic quantum vacuum fluctuations induced by the presence of metric perturbations at the end of inflation. We obtain the amplitude of the corresponding magnetic fields on super-Hubble scales and…

High Energy Physics - Phenomenology · Physics 2007-05-23 Antonio L. Maroto

We examine the evolution of magnetic fields in an expanding fluid composed of matter and radiation with particular interest in the evolution of cosmic magnetic fields. We derive the propagation velocities and damping rates for relativistic…

Astrophysics · Physics 2009-10-28 K. Jedamzik , V. Katalinic , A. Olinto

During the inflationary phase of the early universe, quantum fluctuations in the vacuum generate particles as they stretch beyond the Hubble length. These fluctuations are thought to result in the density fluctuations and gravitational…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jeremy S. Heyl

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

Recent observations of magnetic fields in intergalactic void regions and in high redshift galaxies may indicate that large scale magnetic fields have a primordial origin. If primordial magnetic fields were present soon after the…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-27 Maresuke Shiraishi , Hiroyuki Tashiro , Kiyotomo Ichiki

We study the evolution of an inflation-generated magnetic field, due to its coupling to fluid motions, during cosmological phase transitions. We find that the magnetic field stays almost unchanged on large scales, while on small scales the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Tina Kahniashvili , Axel Brandenburg , Leonardo Campanelli , Bharat Ratra , Alexander G. Tevzadze

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 generation of large-scale magnetic fields is studied in dilaton electromagnetism in inflationary cosmology, taking into account the dilaton's evolution throughout inflation and reheating until it is stabilized with possible entropy…

Astrophysics · Physics 2008-11-26 Kazuharu Bamba , J. Yokoyama

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

We study the effects of a static and uniform magnetic field on the evolution of energy density fluctuations present in a medium. By numerically solving the relativistic Boltzmann-Vlasov equation within the relaxation time approximation, we…

Nuclear Theory · Physics 2023-06-01 Shreyansh S. Dave , Subrata Pal

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

In the past decade, the importance of dissipation and fluctuation to inflationary dynamics has been realized and has led to a new picture of inflation called warm inflation. Although these phenomena are common to condensed matter systems,…

High Energy Physics - Phenomenology · Physics 2009-11-13 Arjun Berera

We present preliminary results on the possible effects that primordial magnetic fields can have for a warm inflation scenario, based on global supersymmetry, with a new-inflation-type potential. This work is motivated by two considerations:…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Gabriella Piccinelli , Angel Sanchez , Alejandro Ayala , Ana Julia Mizher

This letter concentrates on the non-equilibrium evolution of magnetic field structures at the onset of recombination, when the charged particle current densities decay as neutrals are formed. We consider the effect that a decaying magnetic…

Astrophysics · Physics 2009-11-13 Declan A. Diver , Luis F. A. Teodoro

We explore the ways in which primordial magnetic fields influence the thermal and ionization history of the post-recombination universe. After recombination the universe becomes mostly neutral resulting also in a sharp drop in the radiative…

Astrophysics · Physics 2008-11-26 Shiv K. Sethi , Kandaswamy Subramanian

It is shown that gravitating magnetic fields affect the evolution of curvature perturbations in a way that is reminiscent of a pristine non-adiabatic pressure fluctuation. The gauge-invariant evolution of curvature perturbations is used to…

Astrophysics · Physics 2008-11-26 Massimo Giovannini

The mechanism of thermal inflation, a relatively short period of accelerated expansion after primordial inflation, is a desirable ingredient for a certain class of particle physics models if they are not to be in contention with the…

High Energy Physics - Phenomenology · Physics 2015-06-23 Takashi Hiramatsu , Yuhei Miyamoto , Jun'ichi Yokoyama

We consider the evolution of electromagnetic fields coupled to conduction currents during the reheating era after inflation, and prior to the establishing of the proton-electron plasma. We assume that the currents may be described by second…

General Relativity and Quantum Cosmology · Physics 2015-06-23 Esteban Calzetta , Alejandra Kandus

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 study the amplification of electromagnetic vacuum fluctuations induced by the evolution of scalar metric perturbations at the end of inflation. Such perturbations break the conformal invariance of Maxwell equations in…

High Energy Physics - Phenomenology · Physics 2008-11-26 Antonio L. Maroto
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