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Related papers: Sachs equations for light bundles in a cold plasma

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We provide a covariant derivation of plasma physics coupled to gravitation by utilizing the 3+1 formulation of general relativity, including a discussion of the Lorentz force law. We then reduce the system to the spherically symmetric case…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Paul Lasky , Anthony Lun

The Friedmann equation is derived for a Newtonian universe. Changing mass density to energy density gives exactly the Friedmann equation of general relativity. Accounting for work done by pressure then yields the two Einstein equations that…

Astrophysics · Physics 2015-06-24 Thomas F. Jordan

A non-perturbative study on the quantum fluctuations of light ray propagation through a quantum region of spacetime is long overdue. Within the theory of Lorentzian simplicial quantum gravity, we compute the probabilities for a test light…

General Relativity and Quantum Cosmology · Physics 2022-06-14 Ding Jia

The Hubble law, determined from the distance modulii and redshifts of galaxies, for the past 80 years, has been used as strong evidence for an expanding universe. This claim is reviewed in light of the claimed lack of necessary evidence for…

General Physics · Physics 2011-11-22 John G. Hartnett

Band theory for partially coherent light is introduced by using the formalism of second-order classical coherence theory under paraxial approximation. It is demonstrated that the cross-spectral density function, describing correlations…

Optics · Physics 2022-12-21 P. A. Brandão , J. C. A. Rocha

Minkowski spacetime is a convenient setting for the study of the relativistic dynamics of particles and fields in the vacuum. In order to study events that occur in a dielectric or other linear medium, we adopt the familiar continuum…

Classical Physics · Physics 2009-02-27 Michael E. Crenshaw

The cosmological constant (lambda) of general relativity is a natural consequence of embedding Einstein's theory in a five-dimensional theory of the type needed for unification. The exact 5D solution for lambda less than 0 shows waves in…

General Relativity and Quantum Cosmology · Physics 2014-11-04 Paul S. Wesson

We present new numerical cosmological solutions of the Einstein Field Equations. The spacetime is spherically symmetric with a source of dust and radiation approximated as a perfect fluid. The dust and radiation are necessarily non-comoving…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-14 Woei Chet Lim , Marco Regis , Chris Clarkson

We consider light propagation in a spacetime whose kinematics allow weak birefringence, and whose dynamics have recently been derived by gravitational closure. Revisiting the definitions of luminosity and angular diameter distances in this…

General Relativity and Quantum Cosmology · Physics 2017-07-06 Frederic P. Schuller , Marcus C. Werner

Recently it has been shown that despite previous claims the cosmological constant affects light bending. In the present article we study light bending and the advance of Mercury's perihelion in the context of the Newtonian limit of…

General Relativity and Quantum Cosmology · Physics 2010-11-09 H. Miraghaei , M. Nouri-Zonoz

A calculation by Jacobson [1] strongly implies that the field equations which describe gravity are emergent phenomena. In this paper, the method is extended to the case of a non-commutative spacetime. By making use of a non-commutative…

High Energy Physics - Theory · Physics 2015-05-21 Simon Moolman

The Einstein-Vlasov equations govern Einstein spacetimes filled with matter which interacts only via gravitation. The matter, described by a distribution function on phase space, evolves under the collisionless Boltzmann equation,…

General Relativity and Quantum Cosmology · Physics 2019-10-29 Lars Andersson , Mikołaj Korzyński

We formulate a stochastic generalisation of the Schwinger effect, extending pair production to statistically fluctuating gauge-field backgrounds. Our approach captures realistic field configurations that are transient, inhomogeneous, and…

High Energy Physics - Theory · Physics 2026-03-11 Lucas Vicente García-Consuegra , Azadeh Maleknejad

In cosmology based on general relativity, the universe is modeled as a fluid. The transition from the Einstein field equation to its large-scale (cosmological) version is thus analogous to the transition, for a system consisting of a large…

General Physics · Physics 2018-10-18 Gregory Ryskin

The nonlinear coupling between the light beams and non-resonant ion density perturbations in a plasma is considered, taking into account the relativistic particle mass increase and the light beam ponderomotive force. A pair of equations…

Pattern Formation and Solitons · Physics 2009-11-07 P. K. Shukla , R. Fedele , M. Onorato , N. L. Tsintsadze

The transport equations for polarized radiation transfer in non-Riemannian, Weyl-Cartan type space-times are derived, with the effects of both torsion and non-metricity included. To obtain the basic propagation equations we use the tangent…

General Relativity and Quantum Cosmology · Physics 2009-11-11 K. S. Cheng , T. Harko , X. Y. Wang

The purpose of this article is twofold. First, we extend the results presented in [Gabriel Crisnejo and Emanuel Gallo, Phys.Rev.D 97, 124016 (2018)] to stationary spacetimes. Specifically, we show that the Gauss-Bonnet theorem can be…

General Relativity and Quantum Cosmology · Physics 2019-11-27 Gabriel Crisnejo , Emanuel Gallo , Kimet Jusufi

The standard model of cosmology is based on the hypothesis that the Universe is spatially homogeneous and isotropic. When interpreting most observations, this cosmological principle is applied stricto sensu: the light emitted by distant…

General Relativity and Quantum Cosmology · Physics 2024-01-15 Pierre Fleury

The dynamical equations describing the evolution of a self-gravitating fluid of cold dark matter (CDM) can be written in the form of a Schrodinger equation coupled to a Poisson equation describing Newtonian gravity. It has recently been…

Astrophysics · Physics 2009-11-11 C. J. Short , P. Coles

Vacuum polarization in QED in a background gravitational field induces interactions which {\it effectively} modify the classical picture of light rays, as the null geodesics of spacetime. These interactions violate the strong equivalence…

General Relativity and Quantum Cosmology · Physics 2009-11-11 N. Ahmadi , M. Nouri-Zonoz
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