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Related papers: Challenges in Inflationary Magnetogenesis: Constra…

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The simplest gauge invariant models of inflationary magnetogenesis are known to suffer from the problems of either large backreaction or strong coupling, which make it difficult to self-consistently achieve cosmic magnetic fields from…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Ricardo J. Z. Ferreira , Rajeev Kumar Jain , Martin S. Sloth

We study the generation of helical magnetic fields in a model of inflationary magnetogenesis which is free from the strong coupling and back-reaction problems. To generate helical magnetic fields, we add an $f^2 \tilde{F}^{\mu\nu}…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-11 Ramkishor Sharma , Kandaswamy Subramanian , T. R. Seshadri

We study the generation of magnetic fields during inflation making use of a coupling of the inflaton and moduli fields to electromagnetism via the photon kinetic term, and assuming that the coupling is an increasing function of time. We…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-02 Hossein Bazrafshan Moghaddam , Evan McDonough , Ryo Namba , Robert H. Brandenberger

We study the generation of electromagnetic fields during inflation when the conformal invariance of Maxwell's action is broken by the kinetic coupling $f^{2}(\phi)F_{\mu\nu}F^{\mu\nu}$ of the electromagnetic field to the inflaton field…

High Energy Physics - Phenomenology · Physics 2018-10-03 O. O. Sobol , E. V. Gorbar , M. Kamarpour , S. I. Vilchinskii

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

Among primordial magnetogenesis models, inflation is a prime candidate to explain the current existence of cosmological magnetic fields. Assuming conformal invariance to be restored after inflation, their energy density decreases as…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-11 Vittoria Demozzi , Christophe Ringeval

We study the primordial magnetic field generated by the simple model $f^2 FF$ in Starobinsky, $R^2$-inflationary, model. The scale invariant PMF is achieved at relatively high power index of the coupling function, $\left| \alpha \right|…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-21 Anwar Saleh AlMuhammad

The simplest model of primordial magnetogenesis can provide scale-invariant magnetic fields that can explain the present abundances of it in the cosmic scales. Two kinds of solutions of the coupling function can lead to such phenomena and…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Debottam Nandi

By assuming the kinetic coupling $f^{2}(\phi)FF$ of the effective inflaton field $\phi$ with the electromagnetic field, we explore magnetogenesis during the inflation and preheating stages in the Starobinsky model. We consider the case of…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-27 S. Vilchinskii , O. Sobol , E. V. Gorbar , I. Rudenok

Recent blazar observations provide growing evidence for the presence of magnetic fields in the extragalactic regions. While a natural speculation is to associate the production to inflationary physics, it has been known that magnetogenesis…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Tomohiro Fujita , Ryo Namba

In this paper, we discuss the inflationary magnetogenesis scenario, in which the coupling function is introduced to break the conformal invariance of electromagnetic action. Unlike in conventional models, we deduce the Maxwell's equations…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-12 Y. Li , L. Y. Zhang

We study magnetogenesis in axionlike inflation driven by a pseudoscalar field $\phi$ coupled axially to the electromagnetic (EM) field $(\beta/M_{p})\phi F_{\mu\nu}\tilde{F}^{\mu\nu}$ with dimensionless coupling constant $\beta$. A set of…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-20 O. O. Sobol , E. V. Gorbar , S. I. Vilchinskii

We derive a simple model-independent upper bound on the strength of magnetic fields obtained in inflationary and post-inflationary magnetogenesis taking into account the constraints imposed by the condition of weak coupling, back-reaction…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-26 Yuri Shtanov , Mykhailo Pavliuk

While during inflation a phase of increasing gauge coupling allows for a scale-invariant hyperelectric spectrum, when the coupling decreases a flat hypermagnetic spectrum can be generated for typical wavelengths larger than the effective…

General Relativity and Quantum Cosmology · Physics 2021-06-08 Massimo Giovannini

We consider helical coupling to electromagnetism and present a simple scenario of evolution of the coupling function leading to a viable inflationary magnetogenesis without the problem of back-reaction. In this scenario, helical magnetic…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Yuri Shtanov

We consider inflationary magnetogenesis where the conformal symmetry is broken by the term $f^2(\phi) F_{\alpha\beta} F^{\alpha\beta}$. We assume that the magnetic field power spectrum today between 0.1 and $10^4$ Mpc is a power law, with…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-20 Tommi Markkanen , Sami Nurmi , Syksy Rasanen , Vincent Vennin

We investigate inflationary magnetogenesis in a scenario where conformal invariance of electromagnetism is broken through a \emph{non-minimal Yukawa-like coupling between the inflaton and the Ricci scalar}. We account for electromagnetic…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-14 Orlando Luongo , Antonino Giacomo Marino , Tommaso Mengoni

As additional perturbative degrees of freedom, it is known that magnetic fields of inflationary origin can source curvature perturbations on super-Hubble scales. By requiring the magnetic generated curvature to remain smaller than its…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Christophe Ringeval , Teruaki Suyama , Jun'ichi Yokoyama

In this work we compute the production of magnetic fields in models of axion inflation coupled to the hypercharge sector of the Standard Model through a Chern-Simons interaction term. We make the simplest choice of a quadratic inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-26 Peter Adshead , John T. Giblin , Timothy R. Scully , Evangelos I. Sfakianakis

Although inflation is a natural candidate to generate the lengths of coherence of magnetic fields needed to explain current observations, it needs to break conformal invariance of electromagnetism to obtain significant magnetic amplitudes.…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-22 Federico Agustin Membiela
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