English
Related papers

Related papers: Viable inflationary magnetogenesis with helical co…

200 papers

It is shown that the evolution of the (Abelian) gauge coupling during an inflationary phase of de Sitter type drives the growth of the two-point function of the magnetic inhomogeneities. After examining the constraints on the variation of…

Astrophysics · Physics 2009-11-06 Massimo Giovannini

We explore the generation of large-scale magnetic fields from inflation in teleparallelism, in which the gravitational theory is described by the torsion scalar instead of the scalar curvature in general relativity. In particular, we…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-02 Kazuharu Bamba , Chao-Qiang Geng , Ling-Wei Luo

$R^2$-Higgs inflation stands out as one of the best-fit models of Planck data. Using a covariant formalism for the inflationary dynamics and the production of helical gauge fields, we show that the observed baryon asymmetry of the Universe…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-20 Yann Cado , Christoph Englert , Tanmoy Modak , Mariano Quirós

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

Cosmological inflation provides the initial conditions for the structure formation. However, the origin of large-scale magnetic fields cannot be addressed in this framework. The key issue for this long-standing problem is the conformal…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 Debottam Nandi , S. Shankaranarayanan

The existence of large-scale anisotropy can not be ruled out by the cosmic microwave background (CMB) radiation. Over the years, several models have been proposed in the context of anisotropic inflation to account for CMB's cold spot and…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-15 Sourav Pal , Debaprasad Maity , Tuan Q. Do

We discuss the possibility of successful magnetogenesis during inflation by employing the one-loop effective action of massless QED. The action is strictly non-local and results from the long distance fluctuations of massless charged…

General Relativity and Quantum Cosmology · Physics 2016-05-18 Basem Kamal El-Menoufi

We show that maximally helical hypermagnetic fields produced during pseudoscalar inflation can generate the observed baryon asymmetry of the universe via the B+L anomaly in the Standard Model. We find that most of the parameter space of…

High Energy Physics - Theory · Physics 2015-11-11 Mohamed M. Anber , Eray Sabancilar

We explore the generation of large-scale magnetic fields in the so-called moduli inflation. The hypercharge electromagnetic fields couple to not only a scalar field but also a pseudoscalar one, so that the conformal invariance of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-30 Kazuharu Bamba

Motivated by a scenario of magnetogenesis in which a homogeneous magnetic field is generated during inflation, we study the magnetohydrodynamic evolution of the primordial plasma motions for two kinds of initial conditions -- (i) a…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-28 Axel Brandenburg , Ruth Durrer , Yiwen Huang , Tina Kahniashvili , Sayan Mandal , Shinji Mukohyama

The production of the hypermagnetic gyrotropy is investigated under the assumption that the gauge coupling smoothly evolves during a quasi-de Sitter phase and then flattens out in the radiation epoch by always remaining perturbative. In the…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-23 Massimo Giovannini

We investigate the generation of seed magnetic field through the Chern-Simons coupling between the U(1) gauge field and an axion field that commences to oscillate at various epoch, depending on the mass scale. We address axions which begin…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-05 Teerthal Patel , Hiroyuki Tashiro , Yuko Urakawa

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

The origin of magnetic fields observed on both astrophysical and cosmological scales is a compelling problem that has the potential to shed light on the early Universe. We analytically investigate inflationary magnetogenesis in scenarios…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-08 Bill Atkins , Debika Chowdhury , Alisha Marriott-Best , Gianmassimo Tasinato

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

If the conformal invariance of electromagnetism is broken during inflation, then primordial magnetic fields may be produced. If this symmetry breaking is generated by the coupling between electromagnetism and a scalar field---e.g. the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 Robert R. Caldwell , Leonardo Motta , Marc Kamionkowski

[Abridged] As is well known, in order to generate magnetic fields of observed amplitudes during inflation, the conformal invariance of the electromagnetic field has to be broken by coupling it either to the inflaton or to the scalar…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Sagarika Tripathy , Debika Chowdhury , H. V. Ragavendra , Rajeev Kumar Jain , L. Sriramkumar

The anomalous conversion of leptons into baryons during leptogenesis is shown to produce a right-handed helical magnetic field; in contrast, the magnetic field produced during electroweak baryogenesis is known to be left-handed. If the…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 Andrew J. Long , Eray Sabancilar , Tanmay Vachaspati

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

Models of inflation in which the Higgs field is non-minimally coupled to gravity lead, after a recaling of the metric, to a complicated expression for the potential of the inflaton field. Nevertheless, this potential produces the desired…

High Energy Physics - Theory · Physics 2022-06-08 Noureddine Mohammedi
‹ Prev 1 3 4 5 6 7 10 Next ›