English
Related papers

Related papers: Scale-invariant Helical Magnetic Fields from Infla…

200 papers

We present results of a detailed and fully non-linear numerical and analytical investigation of magnetic field evolution from the very earliest cosmic epochs to the present. We find that, under reasonable assumptions concerning the…

Astrophysics · Physics 2009-11-07 Robi Banerjee , Karsten Jedamzik

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 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

A symmetry-breaking phase transition in the early universe could have led to the formation of cosmic defects. Because these defects dynamically excite not only scalar and tensor type cosmological perturbations but also vector type ones,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Kouichirou Horiguchi , Kiyotomo Ichiki , Toyokazu Sekiguchi , Naoshi Sugiyama

We reexamine generation of the primordial magnetic fields, at temperature $T>80$TeV, by applying a consistent kinetic theory framework which is suitably modified to take the quantum anomaly into account. The modified kinetic equation can…

General Relativity and Quantum Cosmology · Physics 2016-09-01 Arun Kumar Pandey , Jitesh R. Bhatt

It is believed that the recent detection of large tensor perturbations strongly favors the inflation scenario in the early universe. This common sense depends on the assumption that Einstein's general relativity is valid at the early…

High Energy Physics - Theory · Physics 2015-06-19 Mingzhe Li

We suggest a new mechanism for generation of large-scale magnetic field in the hot plasma of early universe which is based on the parity violation in weak interactions and depends neither on helicity of matter turbulence resulting in the…

Astrophysics · Physics 2009-11-10 V. B. Semikoz , D. D. Sokoloff

In the framework of Higgs inflation, we consider the electromagnetic field nonminimally coupled to gravity via the parity-preserving $\propto RF^{2}$ and parity-violating $\propto RF\tilde{F}$ terms. Using the perturbation theory to the…

General Relativity and Quantum Cosmology · Physics 2021-08-11 O. O. Sobol , E. V. Gorbar , O. M. Teslyk , S. I. Vilchinskii

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 cosmological inflationary scenarios from a gravitoelectromagnetic theory. Our work is formulated in the light of a recently introduced geometrical Weyl-Invariant scalar-tensor theory of gravity, where the nature of both the…

General Relativity and Quantum Cosmology · Physics 2018-04-10 M. Montes , José Edgar Madriz Aguilar , V. Granados

We characterize magnetic fields produced during electroweak symmetry breaking by non-dynamical numerical simulations based on the Kibble mechanism. The generated magnetic fields were thought to have an energy spectrum $\propto k^3$ for…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 Tanmay Vachaspati , Axel Brandenburg

We propose a simple solution to the magnetogenesis problem based on cyclic cosmology. It is demonstrated that magnetic fields, of sufficient strengths to account for the present observational bounds, can be created in the contracting phase…

General Relativity and Quantum Cosmology · Physics 2018-10-24 Natacha Leite , Petar Pavlović

In our conventional understanding, large-scale magnetic fields are thought to originate from an inverse cascade in the presence of magnetic helicity, differential rotation, or a magneto-rotational instability. However, as recent simulations…

Plasma Physics · Physics 2017-09-20 Kiwan Park

We describe a novel proposal for inflationary magnetogenesis by identifying the non-Abelian sector of Spectator Chromo Natural Inflation (SCNI) with the $\rm{SU(2)}_{\rm L}$ sector of the Standard Model. This mechanism relies on the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-23 Axel Brandenburg , Oksana Iarygina , Evangelos I. Sfakianakis , Ramkishor Sharma

We study the generation and evolution of density perturbations and peculiar velocities due to primordial magnetic fields. We assume that a random magnetic field was present before recombination and follow the field's effect on the baryon…

Astrophysics · Physics 2009-10-22 Eun-jin Kim , Angela Olinto , Robert Rosner

One often resorts to a non-minimal coupling of the electromagnetic field in order to generate magnetic fields during inflation. The coupling is expected to depend on a scalar field, possibly the same as the one driving inflation. At the…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 Debika Chowdhury , L. Sriramkumar , Marc Kamionkowski

We study the evolution of primordial magnetic fields in an expanding cosmic plasma. For this purpose we present a comprehensive theoretical model to consider the evolution of MHD turbulence that can be used over a wide range of physical…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 Tina Kahniashvili , Axel Brandenburg , Alexander G. Tevzadze

We propose that strong magnetic fields should be generated at shock waves associated with formation of galaxies or clusters of galaxies by the Weibel instability, an instability in collisionless plasmas. The strength of the magnetic fields…

Astrophysics · Physics 2009-11-13 Yutaka Fujita , Tsunehiko N. Kato

We constrain a primordial magnetic field (PMF) generated during a phase transition (PT) using the big bang nucleosynthesis bound on the relativistic energy density. The amplitude of the PMF at large scales is determined by the shape of the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-04 Tina Kahniashvili , Alexander G. Tevzadze , Bharat Ratra

Primordial magnetic fields (PMFs) are magnetic fields generated during the early universe. These fields are thought to be the seeds of extragalactic magnetic fields. The origin of PMFs is not well known. Further, if they are indeed sources…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Ganga R. Nair , V. Sreenath
‹ Prev 1 8 9 10 Next ›