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We study the generation of magnetic fields in the Higgs inflation model with the axial coupling in order to break the conformal invariance of the Maxwell action and produce strong magnetic fields. We consider radiatively corrected Higgs…

General Relativity and Quantum Cosmology · Physics 2021-08-17 Mehran Kamarpour

We consider models in which the (transverse) photon mass is non-zero during inflation and drops to zero non-adiabatically at the end of inflation. Through this process, vacuum fluctuations of the photon field are converted into physical,…

We consider an intermediate Dirac-Born-Infeld (DBI) inflationary model in the presence of a minimal measurable length in the theory. We show that, the presence of a minimal measurable length modifies the definitions of the scalar and tensor…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-02 Narges Rashidi , Maryam Roushan , Kourosh Nozari

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

The hot plasma above the electroweak scale contains (hyper) charged scalar particles which are coupled to Abelian gauge fields. Scalars may interact with gravity in a non-conformally invariant way and thus their fluctuations can be…

High Energy Physics - Phenomenology · Physics 2009-10-31 M. Giovannini , M. Shaposhnikov

[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

We consider a non-canonic field in the context of Starobinsky inflation. We work in Einstein-frame. In this frame, the gravitational part of the action is equivalent to the Hilbert-Einstein action, plus a scalar field called scalaron. We…

General Relativity and Quantum Cosmology · Physics 2021-04-28 Salomeh Khoeini-Moghaddam

We propose a novel inflationary scenario in string theory in which the inflaton field is a 'Wilson line' degree of freedom in the worldvolume of a probe Dp-brane, in a warped flux compactification. Kinetic terms for Wilson line fields on…

High Energy Physics - Theory · Physics 2009-02-09 A. Avgoustidis , I. Zavala

We explore cosmological magnetogenesis in the post-inflationary universe, when the inflaton oscillates around its potential minimum and the universe is effectively dominated by cold matter. During this epoch prior to reheating, large-scale…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-29 Takeshi Kobayashi

We propose a new mechanism for magnetic field generation from inflation, by which strong magnetic fields can be generated on cosmological scales. These fields may be observable by cosmic microwave background radition measurements, and may…

Astrophysics · Physics 2009-11-10 Tomislav Prokopec , Ewald Puchwein

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

Primordial magnetic fields could explain the large-scale magnetic fields present in the Universe. Inflation and phase transitions in the early Universe could give rise to such fields with unique characteristics. We investigate the…

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 analyze the spectrum of density perturbations generated in models of the recently discovered "D-cceleration" mechanism of inflation. In this scenario, strong coupling quantum field theoretic effects sum to provide a DBI-like action for…

High Energy Physics - Theory · Physics 2009-11-10 Mohsen Alishahiha , Eva Silverstein , David Tong

The generation of helical magnetic fields during single field inflation due to an axial coupling of the electromagnetic field to the inflaton is discussed. We find that such a coupling always leads to a blue spectrum of magnetic fields…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-12 Rajeev Kumar Jain , Ruth Durrer , Lukas Hollenstein

The post-inflationary evolution of inflation-produced magnetic fields, conventional or not, can change dramatically when two fundamental issues are accounted for. The first is causality, which demands that local physical processes can never…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-01 Christos G. Tsagas

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

We study the variation of the effective fine structure constant alpha for Dirac-Born-Infeld (DBI) type dark energy models. The DBI action based on string theory naturally gives rise to a coupling between gauge fields and a scalar field…

High Energy Physics - Theory · Physics 2014-11-18 Mohammad R. Garousi , M. Sami , Shinji Tsujikawa

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

In models of cosmological inflation motivated by dynamical supersymmetry breaking, the potential driving inflation may be characterized by inverse powers of a scalar field. These models produce observables similar to those typical of the…

High Energy Physics - Phenomenology · Physics 2009-10-31 William H. Kinney , Antonio Riotto
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