Related papers: Magnetic fields from reionisation
We derive the advection of magnetic fields due to gradients in magnetic diffusivity, starting from the magnetic induction equation. We discuss physical examples, and compare our results to those in the literature. Our induction and…
Axions seem ubiquitous in string theories and some of them may be produced non-thermally by heavy scalar decays, contributing to dark radiation. We study various cosmological effects of photons produced from the axionic dark radiation…
Problems and perspectives concerning the existence of large-scale magnetic fields are described. Heeding observations, possible origins and implications of magnetic fields in spiral galaxies and in regular clusters are scrutinized in…
The magnetic field in intergalactic space gives important information about magnetogenesis in the early universe. The properties of this field can be probed by searching for radiation of secondary e$^+ $e$^-$ pairs created by TeV photons,…
The origin of magnetic fields in the Universe is an open problem. Seed magnetic fields possibly produced in early times may have survived up to the present day close to their original form, providing an untapped window to the primeval…
Detailed physical processes of magnetic field generation from density fluctuations in the pre-recombination era are studied. Solving Maxwell equations and the generalized Ohm's law, the evolutions of the net charge density, the electric…
There is strong observational evidence for the presence of large-scale magnetic fields MF in galaxies and clusters, with strength $\sim \mu$G and coherence lenght on the order of Kpc. However its origin remains as an outstanding problem.…
The radiative acceleration of particles and the electrostatic potential fields that arise in low density plasmas hit by radiation produced by a transient, compact source are investigated. We calculate the dynamical evolution and asymptotic…
The local intensity of the 21 cm signal emitted during the Epoch of Reionization that will be mapped by the SKA is modulated by the amount of neutral hydrogen. Consequently, understanding the process of reionization of the intergalactic…
The origin of interstellar and intergalactic magnetic fields remains largely unknown. One possibility is that they are related to the primordial magnetic fields (PMFs) produced by, for instance, the phase transitions of the early Universe.…
Despite their ubiquity, the origin of cosmic magnetic fields remains unknown. Various mechanisms have been proposed for their existence including primordial fields generated by inflation, or amplification and injection by compact…
Magnetic fields are observed beyond the peripheries of optically detected galactic discs, while numerical models of their origin and the typical magnitudes are still absent. Previously, studies of galactic dynamo have avoided considering…
Static synthetic magnetic fields give rise to phenomena including the Lorentz force and the quantum Hall effect even for neutral particles, and they have by now been implemented in a variety of physical systems. Moving towards fully…
The origin of cosmic magnetic fields is widely attributed to the amplification of weak seed fields by turbulent dynamos. However, a critical understanding gap remains between the microscopic generation of these seeds and the macroscopic…
Axions that couple to electromagnetism are produced in the early Universe by, among other channels, freeze-in via the Primakoff process. For sufficiently large axion masses, the same coupling causes the axions to decay into two photons,…
Star-forming galaxies in the early universe provide us with perhaps the most natural way of explaining the reionization of the universe. Current observational results are sufficiently comprehensive, as to allow us to approximately calculate…
Magnetic fields may have been generated in the electroweak phase transition through spontaneous symmetry breaking or through the subsequent dynamical evolution of semiclassical field configurations. Here I demonstrate explicitly how…
Primordial magnetic fields possibly generated in the very early universe are one of the candidates for the origin of magnetic fields observed in many galaxies and galaxy clusters. After recombination, the dissipation process of the…
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…
We investigate the 21-cm signature that may arise from the intergalactic medium (IGM) prior to the epoch of full reionization (z>5). In scenarios in which the IGM is reionized by discrete sources of photoionizing radiation, the neutral gas…