English
Related papers

Related papers: Primordial large-scale electromagnetic fields from…

200 papers

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 investigate the impact of inhomogeneous inflaton perturbations on primordial magnetic fields within the framework of generalized inflationary magnetogenesis models. Extending the Ratra model to general spacetime backgrounds, we analyze…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-28 Yu Li , Shuang Liu , Hang Wang , Yao-Chuan Wang

We propose a novel formalism for inflation from a 5D vacuum state which could explain both, seeds of matter and magnetic fields in the early universe.

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alfredo Raya , Jose Edgar Madriz Aguilar , Mauricio Bellini

Oscillons are massive, long-lived, localized excitations of a scalar field. We show that in a large class of well-motivated single-field models, inflation is followed by self-resonance, leading to copious oscillon generation and a lengthy…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-09 Mustafa A. Amin , Richard Easther , Hal Finkel , Raphael Flauger , Mark P. Hertzberg

The large-scale magnetic fields we observe today in galaxies and galaxy clusters could be the result of a pure quantum effect taking place during inflation, to wit, the creation of particles (photons) out from the vacuum in a curved…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-26 Leonardo Campanelli

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

Magnetic fields have been observed in galaxies, clusters of galaxies and probably in superclusters. While mechanisms exist to generate these in the late universe, it is possible that magnetic fields have existed since very early times. This…

Astrophysics · Physics 2009-12-07 Iain A. Brown

After a brief summary of general relativity and cosmology, we present the basic concepts underlying inflation, the currently best motivated models for the early Universe. We describe the simplest inflation models, based on a single scalar…

General Relativity and Quantum Cosmology · Physics 2008-11-27 David Langlois

We extend some previous attempts to explain the origin and evolution of primordial magnetic fields during inflation induced from a 5D vacuum. We show that the usual quantum fluctuations of a generalized 5D electromagnetic field cannot…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Federico Agustín Membiela , Mauricio Bellini

We use non-linear gauge-invariant perturbation theory to study the interaction of an inflation produced seed magnetic field with density and gravitational wave perturbations in an almost Friedmann-Lema\^itre-Robertson-Walker (FLRW)…

General Relativity and Quantum Cosmology · Physics 2012-10-23 Bishop Mongwane , Peter K. S. Dunsby , Bob Osano

Large scale magnetic fields seem to be present in almost all astrophysical systems and scales from planets to superclusters of galaxies and in very low density intergalactic media. The upper limit of primordial magnetic fields (PMF) has…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-26 Anwar Saleh AlMuhammad

Sufficiently large seeds for generating the observed (inter)galactic magnetic fields emerge naturally in string cosmology from the amplification of electromagnetic vacuum fluctuations due to a dynamical dilaton background. The success of…

High Energy Physics - Theory · Physics 2009-10-28 M. GasperinI , M. Giovannini , G. Veneziano

The 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…

High Energy Physics - Phenomenology · Physics 2009-11-10 Kazuharu Bamba , J. Yokoyama

Using a semiclassical approach to Gravitoelectromagnetic Inflation (GEMI), we study the origin and evolution of seminal inflaton and electromagnetic fields in the early inflationary universe from a 5D vacuum state. The difference with other…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-20 Federico Agustin Membiela , Mauricio Bellini

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

The primordial gravitational waves (\textbf{PGW}) have been generated by inflationary amplification of the primordial (quantum) fluctuations. It is true that they have not been recorded directly so far, but their spectrum can help a lot in…

General Relativity and Quantum Cosmology · Physics 2022-02-23 Taimur Mohammadi , Behrooz Malekolkalami , Khabat Ghamari

This paper concerns the generation and evolution of the cosmological (large-scale $\sim Mpc$) magnetic fields in an inflationary universe. The universe during inflation is represented by de Sitter space-time. We started with the Maxwell…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Zuxiang Dai

We examine cosmological perturbations in a dynamical theory of inflation in which an Abelian gauge field couples directly to the inflaton, breaking conformal invariance. When the coupling between the gauge field and the inflaton takes a…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-13 Timothy R. Dulaney , Moira I. Gresham

We show that, during false vacuum inflation, a primordial magnetic field can be created, sufficiently strong to seed the galactic dynamo and generate the observed galactic magnetic fields. Considering the inflaton dominated regime, our…

Astrophysics · Physics 2010-11-30 A. C. Davis , K. Dimopoulos

The generation of magnetic fields during inflation in an electromagnetic model with a non-local form factor in Maxwell`s action is studied. The equations of motion for the electromagnetic field are derived and solved. It is found that the…

General Relativity and Quantum Cosmology · Physics 2023-11-28 E. V. Gorbar , T. V. Gorkavenko , V. M. Gorkavenko , O. M. Teslyk