Related papers: Electromagnetic fields and charges in expanding un…
We derive, in a manifestly covariant and electromagnetic gauge independent way, the evolution law of the electric field $E^\alpha = Ee^\alpha\ (e^\alpha e_\alpha=1)$, relative to an arbitrary set of instantaneous observers along a null…
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 present a five dimensional unified theory of gravity and electromagnetism which leads to modified Maxwell equations, suggesting a new origin for galactic magnetic fields. It is shown that a region with nonzero scalar curvature would…
We perform a study to describe motion of charged particles under the influence of electromagnetic and gravitational fields of a slowly rotating wormhole with nonvanishing magnetic moment. We present analytic expression for potentials of…
Following renewed interest, the problem of whether the cosmological expansion affects the dynamics of local systems is reconsidered. The cosmological correction to the equations of motion in the locally inertial Fermi normal frame (the…
By using the 3+1 point of view and parametrized Minkowski theories we develop the theory of {\it non-inertial} frames in Minkowski space-time. The transition from a non-inertial frame to another one is a gauge transformation connecting the…
In this paper, we have investigated the density perturbations and cosmological evolution in the FLRW universe in presence of a cosmic magnetic field, which may be assumed to mimic primordial magnetic fields. Such magnetic fields have…
Most of the baryonic matter in the Universe is permeated by magnetic fields which affect many, if not most, of astrophysical phenomena both, in compact sources and in diffuse gas. Recent years have been marked by a worldwide surge of…
We investigate the cosmological dynamics induced by nonlinear electrodynamics in a homogeneous and isotropic universe, focusing on the role of primordial electromagnetic fields with random spatial orientations. Building upon a…
The possibility to avoid the cosmic initial singularity as a consequence of nonlinear effects on the Maxwell eletromagnetic theory is discussed. For a flat FRW geometry we derive the general nonsingular solution supported by a magnetic…
We elaborate on the proposal that the observed acceleration of the Universe is the result of the backreaction of cosmological perturbations, rather than the effect of a negative-pressure dark-energy fluid or a modification of general…
We study effects of noncommutativity on the phase space generated by a non-minimal scalar field which is conformally coupled to the background curvature in an isotropic and homogeneous FRW cosmology. These effects are considered in two…
As is known the repulsion of the volume elements of an uniformly accelerating charge or a charge supported in an uniform gravitational field accounts for the electromagnetic contribution to the charge's inertial and gravitational mass,…
A method to study electromagnetic (EM) effects generated by a straight null cosmic string moving in classical EM fields is suggested. The string is shown to induce an additional EM field which can be described as a solution to homogeneous…
We revisit in the framework of the classical theory the problem of the accelerated motion of an electron, taking into account the effect of the radiation emission. We present results for the momentum and energy of the electromagnetic field…
Cosmological consequences of the nonsymmetric gravitational theory (NGT) are studied. The structure of the NGT field equations is analyzed for an inhomogeneous and anisotropic universe, based on the spherically symmetric field equations. It…
Large scale magnetic fields pervade the cosmic environment where the astrophysical black holes are often embedded and influenced by the mutual interaction. In this contribution we outline the appropriate mathematical framework to describe…
We first investigate the form the General Relativity Theory would have taken had the gravitational mass and the inertial mass of material objects been different. We then extend this analysis to electromagnetism and postulate an equivalence…
Defining the electric and magnetic field vectors in curved spacetime requires a proper choice of the observer's frame four-vector. Related literature shows that this fundamental issue in physics still needs to be properly resolved. In…
The effect of nonzero extent of an electric charge is considered within the assumption that the structure of the charge at rest is spherically-symmetric and the current vector is linear in the acceleration.