Related papers: Seminal Electromagnetic fields from preinflation
Within the framework of loop quantum cosmology, there exists a semi-classical regime where spacetime may be approximated in terms of a continuous manifold, but where the standard Friedmann equations of classical Einstein gravity receive…
The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related…
This paper explores various aspects and implications of the initial configuration of the Standard Model (SM) Higgs field at the beginning of our Universe. It is well known that the SM Higgs field features a deeper, more stable minimum at…
We discuss the evolution of cosmological magnetic fields from the early universe to the present. We review different scenarios for magnetogenesis in the early universe and follow the subsequent evolution of these fields as the universe…
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 this paper we propose a novel unified cosmological model that connects a pre-inflationary epoch, starting at the Planckian time, with the onset of inflation within a single scalar-field framework. The pre-inflationary phase is…
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…
We review current ideas on the origin of galactic and extragalactic magnetic fields. We begin by summarizing observations of magnetic fields at cosmological redshifts and on cosmological scales. These observations translate into constraints…
Simple exact solutions presented here describe the universes which spatial geometries are asymptotically homogeneous and isotropic near the initial singularity, but which evolution goes under the influence of primordial magnetic fields. In…
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…
The origin of our universe's cosmological magnetic fields remains a mystery. In this study, we consider whether these magnetic fields could have been generated in the early universe by a population of charged, spinning primordial black…
The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…
The pre-inflationary evolution of the universe describes the beginning of the expansion from a static initial state, such that the Hubble parameter is initially zero, but increases to an asymptotic constant value, in which it could achieve…
A new model of nonlinear electromagnetic fields possessing a dimensional parameter $\beta$ is proposed. Electromagnetic fields are considered as the source of the gravitation field and accelerated expansion of the universe is driven by…
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…
In the framework of the Connes-Lott model based on noncommutative geometry, the basic features of a gauge theory in the presence of gravity are reviewed, in order to show the possible physical relevance of this scheme for inflationary…
Based on an earlier introduced new class of generalized gravity-matter models defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold, we…
During the inflationary phase of the early universe, quantum fluctuations in the vacuum generate particles as they stretch beyond the Hubble length. These fluctuations are thought to result in the density fluctuations and gravitational…
Scalar-tensor theory of gravity with non-minimal coupling is a fairly good candidate for dark energy, required to explain late-time cosmic evolution. Here we study the very early stage of evolution of the universe with a modified version of…
It is widely believed that primordial magnetic fields are dramatically diluted by the expansion of the universe. As a result, cosmological magnetic fields with residual strengths of astrophysical relevance are generally sought by going…