Related papers: Primordial Magnetic Fields From String Cosmology
We investigate the generation of curvature and isocurvature (dilaton, moduli and axion) perturbations in a general class of axion-dilaton-moduli models,including the pre-big bang scenario. Allowing for an arbitrary coupling constant between…
We demonstrate that the Biermann battery mechanism for the creation of large scale magnetic fields can arise in a simple model protogalaxy. Analytic calculations and numerical simulations follow explicitly the generation of vorticity (and…
We investigate the generation of magnetic field by the Biermann battery in cosmological ionization fronts, using new simulations of the reionization of the universe by stars in protogalaxies. Two mechanisms are primarily responsible for…
Despite the widespread presence of magnetic fields, their origin, evolution and role are still not well understood. Primordial magnetism sounds appealing but is not problem free. The magnetic implications for the large-scale structure of…
The existence of large-scale magnetic fields in galaxies is well established, but there is no accepted mechanism for generating a primordial field which could grow into what is observed today. We discuss a model which attempts to account…
A magnetic field, coherent over the horizon size at the decoupling and strong enough to rotate the polarization plane of the CMBR, can be generated from the electromagnetic vacuum fluctuations amplified by the space-time evolution of the…
There is a reformulation of magnetohydrodynamics in which the fundamental dynamical quantities are the positions and velocities of the lines of magnetic flux in the plasma, which turn out to obey equations of motion very much like ideal…
I review a number of particle-physics models that lead to the creation of magnetic fields in the early universe and address the complex problem of evolving such primordial magnetic fields into the fields observed today. Implications for…
We study primordial electromagnetic fields in effective actions of string theory. In contrast to a conventional scenario of producing primordial electromagnetic fields induced by the axion inflation, we deal with the Dirac-Born-Infeld…
The origin of magnetic fields in clusters of galaxies is still an unsolved problem, which is largely due to our poor understanding of initial seed magnetic fields. If the seed magnetic fields have primordial origins, it is likely that…
Primordial magnetic fields seem to be a generic relic of phase transitions in the early universe. We consider a primordial electromagnetic field formed as a result of a second-order phase transition, and show that it is stable to thermal…
Astrophysical processes can contribute to magnetic fields within cosmic voids either through magnetized outflows from the astrophysical large-scale structure or through superposition of dipolar contributions from individual galaxies. Such…
We explore the possibility of generating large-scale magnetic fields from second-order cosmological perturbations during the pre-recombination era. The key process for this is Thomson scattering between the photons and the charged particles…
The cosmic string theory for cosmological fluctuations is a good example of healthy scientific progress in cosmology. It is a well defined physically motivated model that has been tested by cosmological observations and has been ruled out…
Weak magnetic fields must have existed in the early Universe, as they were sourced by the cross product of electron density and temperature gradients through the Biermann-battery mechanism. In this paper we calculate the magnetic fields…
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,…
The creation of large scale magnetic fields is studied in an inflationary universe where electrodynamics is assumed to be nonlinear. After inflation ends electrodynamics becomes linear and thus the description of reheating and the…
Large scale primordial magnetic fields (PMFs) threading the intergalactic medium are observed ubiquitously in the Universe playing a key role in the cosmic evolution. Their origin is still debated constituting a very active field of…
This review concerns the origin and the possible effects of magnetic fields in the early Universe. We start by providing to the reader with a short overview of the current state of art of observations of cosmic magnetic fields. We then…
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…