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We study a non-uniformly rotating universe outside a Schwarzschild black hole by generating a time-dependent manifold of revolution around a straight line. In this simple model where layers of spherical shells of the universe non-uniformly…

General Relativity and Quantum Cosmology · Physics 2014-03-04 Vee-Liem Saw

The influence of the medium on the gravitational deflection of light rays is widely discussed in literature for the simplest non-trivial case: cold non-magnetized plasma. In this article, we generalize these studies to the case of an…

General Relativity and Quantum Cosmology · Physics 2021-05-19 Oleg Yu. Tsupko

Post-Newtonian theory was instrumental in conducting the critical experimental tests of general relativity and in building the astronomical ephemerides of celestial bodies in the solar system with an unparalleled precision. The cornerstone…

General Relativity and Quantum Cosmology · Physics 2012-09-06 Sergei Kopeikin

Quantized space described by time reversal invariant and rotationally invariant noncommutative algebra of canonical type is studied. A particle in uniform field is considered. We find exactly the energy of a particle in uniform field in the…

High Energy Physics - Theory · Physics 2021-02-22 Kh. P. Gnatenko , Kh. I. Stakhur , A. V. Kryzhova

We study the electromagnetic field equations on an arbitrary quantum curved background in the semiclassical approximation of Loop Quantum Gravity. The effective interaction hamiltonian for the Maxwell and gravitational fields is obtained…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Carlos Kozameh , Florencia Parisi

A mixture of relativistic gases of non-disparate rest masses in a Schwarzschild metric is studied on the basis of a relativistic Boltzmann equation in the presence of gravitational fields. A BGK-type model equation of the collision operator…

General Relativity and Quantum Cosmology · Physics 2014-04-15 Gilberto M. Kremer

We develop a thermal description for photon modes within the context of bouncing universe. Within this study, we start with a Lorentz-breaking dispersion relation which accounts for modified Friedmann equations with a bounce solution. We…

High Energy Physics - Theory · Physics 2022-01-27 A. A. Araújo Filho , A. Yu. Petrov

We propose that in time dependent backgrounds the holographic principle should be replaced by the generalized second law of thermodynamics. For isotropic open and flat universes with a fixed equation of state, the generalized second law…

High Energy Physics - Theory · Physics 2009-10-31 Richard Easther , David A. Lowe

In the article, the deformation of special relativity within the frame of conformable derivative is formulated. Within this context, the two postulates of the theory were re-stated. And, the addition of velocity laws were derived and used…

Classical Physics · Physics 2022-08-31 Ahmed Al-Jamel , Mohamed. Al-Masaeed , Eqab. M. Rabei , Dumitru Baleanu

Given the dimensions (including thickness) of a galaxy, and its rotation profile, a method is shown that finds the mass and density distributions in the defined envelope that will cause that rotation profile with near-exact speed matches.…

Astrophysics · Physics 2007-05-23 Kenneth F. Nicholson

In conventional Maxwell--Lorentz electrodynamics, the propagation of light is influenced by the metric, not, however, by the possible presence of a torsion T. Still the light can feel torsion if the latter is coupled nonminimally to the…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Guillermo F. Rubilar , Yuri N. Obukhov , Friedrich W. Hehl

We consider quantum scattering of particles in media exhibiting strong dispersion degeneracy. In particular, we study flat-banded lattices and linearly dispersed energy bands. The former constitute a prime example of single-particle…

Quantum Gases · Physics 2017-04-05 Manuel Valiente , Nikolaj Thomas Zinner

In this paper we present a new model for modeling the diffusion and relative dispersion of particles in homogeneous isotropic turbulence. We use an Heisenberg-like Hamiltonian to incorporate spatial correlations between fluid particles,…

Fluid Dynamics · Physics 2012-12-18 Thomas Burgener , Dirk Kadau , Hans Jürgen Herrmann

The analysis of the Helmholtz equation is shown to lead to an exact Hamiltonian system of equations describing in terms of ray trajectories a very wide family of wave-like phenomena (including diffraction and interference) going much beyond…

Quantum Physics · Physics 2008-09-16 A. Orefice , R. Giovanelli , D. Ditto

We derive the fully relativistic Ohm's law for an electron-positron plasma. The absence of non-resistive terms in Ohm's law and the natural substitution of the 4-velocity for the velocity flux in the relativistic bulk plasma equations do…

Astrophysics · Physics 2009-10-22 Eric G. Blackman , George B. Field

Here, we introduce a stochastic partial differential equation (SPDE) formulation driven by temporally correlated noise to describe light propagation beyond the standard Markov approximation. By representing the squared refractive index…

Optics · Physics 2026-03-17 Chaoran Wang , Jinquan Qi , Shuang Liu , Chenjin Deng , Shensheng Han

Consistency relations involving the soft limit of the (n + 1)-correlator functions of dark matter and galaxy overdensities can be obtained, both in real and redshift space, thanks to the symmetries enjoyed by the Newtonian equations of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Alexandros Kehagias , Jorge Noreña , Hideki Perrier , Antonio Riotto

Here we study novel effects associated with electromagnetic wave propagation in a Robertson-Walker universe and the Schwarzschild spacetime with a small amount of metric stochasticity. We find that localization of electromagnetic waves…

General Relativity and Quantum Cosmology · Physics 2016-08-25 B. L. Hu , K. Shiokawa

The magnetic field due to an axially symmetric, hot and highly conducting plasma, taken as an ideal magnetohydrodynamic fluid, surrounding a slow rotating compact gravitational object is studied within the context of Einstein-Maxwell field…

General Relativity and Quantum Cosmology · Physics 2017-10-02 Babur M. Mirza

We define the stretched future light cone, a timelike hypersurface composed of the worldlines of radially accelerating observers with constant and uniform proper acceleration. By attributing temperature and entropy to this hypersurface, we…

High Energy Physics - Theory · Physics 2018-08-29 Maulik Parikh , Andrew Svesko