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Related papers: Relaxing the limits on inflationary magnetogenesis

200 papers

We investigate the generation of magnetic fields from inflation, which occurs via breakdown of the conformal invariance of the electromagnetic (EM) field, when coupled with the Ricci scalar and the Gauss-Bonnet invariant. For the case of…

General Relativity and Quantum Cosmology · Physics 2021-04-14 Kazuharu Bamba , E. Elizalde , S. D. Odintsov , Tanmoy Paul

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

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

The interplay among the possible variation of gauge coupling and the inflationary dynamics is investigated in a simplified toy model. Depending upon various parameters (scalar mass, curvature scale at the end of inflation and at the onset…

Astrophysics · Physics 2007-05-23 Massimo Giovannini

The theory of reheating of the Universe after inflation is developed. The transition from inflation to the hot Universe turns out to be strongly model-dependent and typically consists of several stages. Immediately after inflation the field…

High Energy Physics - Theory · Physics 2009-09-29 Lev Kofman , Andrei Linde , Alexei Starobinsky

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

In this thesis, we aim to investigate the mechanisms underlying the genesis of magnetic fields in the Universe and explore their potential in addressing the matter-antimatter asymmetry. We construct consistent models that generate the…

General Relativity and Quantum Cosmology · Physics 2024-03-21 Ashu Kushwaha

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 present generic bounds on magnetic fields produced from cosmic inflation. By investigating field bounds on the vector potential, we constrain both the quantum mechanical production of magnetic fields and their classical growth in a model…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-10 Daniel Green , Takeshi Kobayashi

Cosmological magnetic fields pervade the entire universe, from small to large scales. Since they apparently extend into the intergalactic medium, it is tantalizing to believe that they have a primordial origin, possibly being produced…

High Energy Physics - Theory · Physics 2015-06-23 Gianmassimo Tasinato

We propose a novel mechanism for significantly enhancing the amplitude of primordial electromagnetic fields during inflation. Similar to existing proposals, our idea is based on parametric resonance effects due to…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Misao Sasaki , Valeri Vardanyan , Vicharit Yingcharoenrat

There has been a growing evidence for the existence of magnetic fields in the extra-galactic regions, while the attempt to associate their origin with the inflationary epoch alone has been found extremely challenging. We therefore take into…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Tomohiro Fujita , Ryo Namba , Yuichiro Tada , Naoyuki Takeda , Hiroyuki Tashiro

The inflationary production of magnetic field seeds for galaxies is discussed. The analysis is carried out by writing the wave equation of the electromagnetic field in curved spacetimes. The conformal invariance is broken by taking into…

General Relativity and Quantum Cosmology · Physics 2009-11-10 G. Lambiase , A. R. Prasanna

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

We consider a k-essence model in which a single scalar field can be responsible for both primordial inflation and the present observed acceleration of the cosmological background geometry, while also admitting a nonsingular de Sitter…

High Energy Physics - Theory · Physics 2024-01-17 Alexsandre L. Ferreira Junior , Nelson Pinto-Neto , Jorge Zanelli

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

Primordial magnetogenesis is an intriguing possibility to explain the origin of intergalactic magnetic fields (IGMFs). However, the baryon isocurvature problem has recently been pointed out, ruling out all magnetogenesis models operating…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-08 Kazuki Yanagihara , Fumio Uchida , Tomohiro Fujita , Shinji Tsujikawa

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

[Abridged] We analyze the evolution of superhorizon-scale magnetic fields from the end of inflation till today. Whatever is the mechanism responsible for their generation during inflation, we find that a given magnetic mode with wavenumber…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-09 Leonardo Campanelli

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