Related papers: Cosmological Magnetic Fields from Inflation and Ba…
We reconsider magnetogenesis in the context of three-form inflation, and its backreaction. In particular, we focus on first order perturbation theory during inflation and subsequent radiation era: we discuss the consistency of the…
Recently observational lower bounds on the strength of cosmic magnetic fields were reported, based on gamma-ray flux from distant blazars. If inflation is responsible for the generation of such magnetic fields then the inflation energy…
Several mechanisms have been proposed to generate primordial magnetic fields and it is often assumed that magnetic fields are not affected by a sharp drop in ionization rate due to the cosmic recombination. We investigate the validity of…
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…
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…
The origin of the substantial magnetic fields that are found in galaxies and on even larger scales, such as in clusters of galaxies, is yet unclear. If the second-order couplings between photons and electrons are considered, then…
The $R^2$ term in the Starobinsky inflationary model can be regarded as a leading quantum correction to the gravitational effective action. We assume that parity-preserving and parity-violating (axial) non-minimal couplings between…
We study the electromagnetic field production during preheating after hybrid inflation in a model with the field content of the Standard Model, coupled to a singlet inflaton. We find that very soon after symmetry breaking our system enters…
We propose a novel mechanism for significantly enhancing the amplitude of primordial electromagnetic fields during inflation. Similar to existing proposals, our idea is based on parametric resonance effects due to…
If the B-mode signal in the CMB polarization seen by the BICEP2 experiment is confirmed, it has dramatic implications for models of inflation. The result is also in tension with Planck limits on standard inflationary models. It is therefore…
A model of nonlinear electrodynamics with a dimensional parameter $\beta$ is considered. Electromagnetic fields are the source of the gravitation field and inflation of the universe. We imply that the universe is filled by stochastic…
Different mechanisms which may possibly explain existence of magnetic fields on astronomically large scales are described. A recently suggested model of magnetic fields generation slightly before hydrogen recombination is discussed in more…
We discuss the generation of primordial magnetic fields during inflation in the dilaton-axion electromagnetism, in which the dilaton and axion dynamics are introduced in terms of two time dependent functions of the cosmic scale factor,…
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…
We calculate particle production during inflation and in the early stages of reheating after inflation in models with a charged scalar field coupled to Abelian and non-Abelian gauge fields. A detailed analysis of the power spectra of…
In most of the literature on evolution of cosmological magnetic fields, it is found that large-scale magnetic fields evolve as $B^{2}\propto a^{-4}$ (adiabatic magnetic decay) where $a$ is the cosmological scale factor and $B$ is the…
Magnetic fields appear to be present in essentially all astrophysical environments, including galaxies, clusters of galaxies and voids. There are both observational and theoretical motives for considering the possibility of their origin…
A non-conformally invariant coupling between the inflaton and the photon in the minimal Lorentz-violating standard model extension is analyzed. For specific forms of the Lorentz-violating background tensor, the strong-coupling and…
In this paper we study the generation of primordial perturbations in a cosmological setting of bigravity during inflation. We consider a model of bigravity which can reproduce the $\Lambda$CDM background and large scale structure and a…
We discuss generation of magnetic field from cosmological perturbations. We consider the evolution of three component plasma (electron, proton and photon) evaluating the collision term between elecrons and photons up to the second order.…