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We explore the intimate connection between spacetime geometry and electrodynamics. This link is already implicit in the constitutive relations between the field strengths and excitations, which are an essential part of the axiomatic…

General Relativity and Quantum Cosmology · Physics 2017-02-14 Francisco Cabral , Francisco S. N. Lobo

The electromagnetic fields in Maxwell's theory satisfy linear equations in the classical vacuum. This is modified in classical non-linear electrodynamic theories. To date there has been little experimental evidence that any of these…

Mathematical Physics · Physics 2015-05-14 T. Dereli , R. W. Tucker

Asymptotic properties of electromagnetic waves are studied within the context of Friedmann-Robertson-Walker (FRW) cosmology. Electromagnetic fields are considered as small perturbations on the background spacetime and Maxwell's equations…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Nader Haghighipour

We construct the effective field theory of a perfect fluid in the early universe. Focusing on the case where the fluid has the equation of state of radiation, we show that it may lead to corrections to the background dynamics that can…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Bruno Balthazar , Pedro G. Ferreira

We review the possible mechanisms for the generation of cosmological magnetic fields, discuss their evolution in an expanding Universe filled with the cosmic plasma and provide a critical review of the literature on the subject. We put…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 R. Durrer , A. Neronov

We review the theory of quantum fields propagating in an arbitrary, classical, globally hyperbolic spacetime. Our review emphasizes the conceptual issues arising in the formulation of the theory and presents known results in a…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Stefan Hollands , Robert M. Wald

We study in detail the electromagnetic fields and the Poynting flux in the case of a uniformly accelerated charge, in order to examine whether such a charge does `emit' radiation, especially in view of the widely accepted fact that there is…

General Physics · Physics 2023-01-04 Ashok K. Singal

We examine the mode functions of the electromagnetic field on spherically symmetric backgrounds with special attention to the subclass which allows for the foliation as open Friedmann-Lemaitre (FL) spacetime. It is well-known that in…

General Relativity and Quantum Cosmology · Physics 2012-06-21 Julian Adamek , Claudia de Rham , Ruth Durrer

We study inflation and late-time acceleration in the expansion of the universe in non-minimal electromagnetism, in which the electromagnetic field couples to the scalar curvature function. It is shown that power-law inflation can be…

Astrophysics · Physics 2009-06-23 Kazuharu Bamba , Sergei D. Odintsov

We consider electromagnetic field quantization in an expanding universe. We find that the covariant (Gupta-Bleuler) method exhibits certain difficulties when trying to impose the quantum Lorenz condition on cosmological scales. We thus…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-21 Jose Beltran Jimenez , Antonio L. Maroto

In this paper Maxwell equations are used to analyze the propagation of oscillating electric and magnetic fields from a moving electric dipole source. The results show that both the magnetic field and electric fields generated propagate…

General Physics · Physics 2007-05-23 William D. Walker

In this work we consider an extended electromagnetic theory in which the scalar state which is usually eliminated by means of the Lorenz condition is allowed to propagate. This state has been shown to generate a small cosmological constant…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-01 Jose Beltran Jimenez , Antonio L. Maroto

We review spacetime dynamics in the presence of large-scale electromagnetic fields and then consider the effects of the magnetic component on perturbations to a spatially homogeneous and isotropic universe. Using covariant techniques, we…

Astrophysics · Physics 2008-11-26 J. D. Barrow , R. Maartens , C. G. Tsagas

This paper is devoted to study the effects of electromagnetic on the collapse and expansion of anisotropic gravitating source. For this purpose, we have evaluated the generating solutions of Einstein-Maxwell field equations with spherically…

General Relativity and Quantum Cosmology · Physics 2015-06-18 G. Abbas

The present thesis is focused on the study of FLRW cosmology in modified gravities and with scalar fields. The mystery of dark energy has made that the last decade, many efforts in theoretical physics have been focused on the explanation of…

High Energy Physics - Theory · Physics 2011-04-06 Diego Sáez-Gómez

We consider non-Lorentzian expansions, Galilean and Carrollian, of the Lorentz force equation in which both the particle position and the electro-magnetic field are expanded. There are two well-known limits in the case of a constant field,…

High Energy Physics - Theory · Physics 2023-10-25 José Luis V. Cerdeira , Joaquim Gomis , Axel Kleinschmidt

Gravity field theory and electromagnetic field theory are well established and confirmed by experiments. The Schwarzschild metric and Kerr Metric of Einstein field equation shows that the spatial differential of time gauge is the gravity…

General Physics · Physics 2007-05-23 Xiao Jianhua

In earlier papers we showed that a frame dependent effective action motivated by the postulates of three-space general coordinate invariance and Weyl scaling invariance exactly mimics a cosmological constant in Friedmann-Robertson-Walker…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-25 Stephen L. Adler

Force-free electrodynamics is the theoretical paradigm used to describe electromagnetic fields in a region where the inertia of plasma is negligible compared to the strength of the electromagnetic field. While these fields are studied…

General Relativity and Quantum Cosmology · Physics 2024-03-18 Rakshak Adhikari , Govind Menon , Mikhail V. Medvedev

This note represents a stepping stone from the discovery of the precise mathematical formula for electromagnetic field generated by a moving point charge, the amended Feynman formula, see Bogdan arXiv:0909.5240, and leading to the to the…

Mathematical Physics · Physics 2009-10-07 Victor M. Bogdan
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