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The consistent theoretical description of gravitational Hall-MHD (G-Hall-MHD) equilibria is of fundamental importance for understanding the phenomenology of accretion disks (AD) around compact objects (black holes, neutron stars, etc.). The…

Astrophysics · Physics 2009-11-13 C. Cremaschini , A. Beklemishev , J. Miller , M. Tessarotto

In the context of the teleparallel equivalent of general relativity the concept of gravitational pressure and gravitational energy-momentum arisen in a natural way. In the case of a Friedmann-Lemaitre-Robertson-Walker space FLRW we obtain…

General Relativity and Quantum Cosmology · Physics 2018-02-19 J. F. da Rocha-Neto , B. R. Morais

Observers at rest in a stationary spacetime flat at infinity can measure small amounts of rest-mass+internal energies+kinetic energies+pressure energy in a small volume of fluid attached to a local inertial frame. The sum of these small…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Joseph Katz

We consider a static spherically symmetric charged anisotropic fluid source of finite physical radius (\sim 10^{-16} cm) by introducing a scalar variable \Lambda dependent on the radial coordinate r under general relativity. From the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Saibal Ray , Sumana Bhadra

It is shown that the gravity acceleration just above a chamber filled with gas or plasma at ultra-low pressure can be strongly reduced by applying an Extra Low-Frequency (ELF) electromagnetic field across the gas or the plasma. This…

General Physics · Physics 2013-12-03 Fran De Aquino

The Machian cosmological solution satisfying $\phi =O(\rho /\omega)$ for the perfect-fluid with negative pressure is discussed. When the coefficient of the equation of state $\gamma \to -1/3$, the gravitational constant approaches to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. Miyazaki

The lack of a well-established solution for the gravitational energy problem might be one of the reasons why a clear road to quantum gravity does not exist. In this paper, the gravitational energy is studied in detail with the help of the…

General Relativity and Quantum Cosmology · Physics 2023-08-25 J. B. Formiga , João Duarte

We use direct numerical simulations to investigate fluid-solid interactions in suspensions of rigid fibres settling under gravity in a quiescent fluid. The solid-to-fluid density ratio is $\mathcal{O}(100)$, while the Galileo number ($Ga$)…

Fluid Dynamics · Physics 2025-12-09 Alessandro Chiarini , Emanuele Gallorini , Marco Edoardo Rosti

The gravitational mass-shift effect is investigated in the framework of the standard model with the energy cutoff regularization both for stationary and non-stationary backgrounds at the one-loop level. The problem concerning singularity of…

General Relativity and Quantum Cosmology · Physics 2012-02-21 P. O. Kazinski

It is noticed that the total relative density of mass in the Universe Omega_tot should exceed 1, i.e. Omega_tot=1+f^2/6 according to the field relativistic theory of gravity (RTG), which is free of the cosmological singularity and which…

Astrophysics · Physics 2009-11-07 S. S. Gershtein , A. A. Logunov , M. A. Mestvirishvili

If a magnetic field is frozen into a plasma that undergoes spherical compression then the magnetic field B varies with the plasma density \rho according to B \propto \rho^{2/3}. In the gravitational collapse of cosmological density…

Astrophysics · Physics 2007-05-23 Emma J. King , Peter Coles

We discuss magnetic pressure and density fluctuations in strongly turbulent isothermal MHD flows in "1+2/3" dimensions. We first consider "simple" nonlinear MHD waves, which allow us show that the slow and fast modes have different…

Astrophysics · Physics 2007-05-23 Thierry Passot , Enrique Vazquez-Semadeni

We discuss the effective metric produced in superfluid 3He-A by such topological objects as radial disgyration and monopole. In relativistic theories these metrics are similar to that of the local string and global monopole correspondingly.…

Condensed Matter · Physics 2009-10-31 G. E. Volovik

We study exact solutions of the Einstein-Maxwell equations for the interior gravitational field of static spherically symmetric charged compact spheres. The spheres consist of an anisotropic fluid with a charge distribution that gives rise…

General Relativity and Quantum Cosmology · Physics 2022-02-18 Krsna Dev

The equivalence principle in combination with the special relativistic equivalence between mass and energy, $E=mc^2$, is one of the cornerstones of general relativity. However, for composite systems a long-standing result in general…

General Relativity and Quantum Cosmology · Physics 2019-05-22 Magdalena Zych , Łukasz Rudnicki , Igor Pikovski

Static observers remain on Killing-vector world lines and measure the rest-mass+kinetic energies of particles moving past them, and the flux of that mechanical energy through space and time. The total mechanical energy is the total flux…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Joseph Katz , Donald Lynden-Bell , Jiri Bicak

Cosmology is investigated within a new, scalar theory of gravitation, which is a preferred-frame bimetric theory with flat background metric. Before coming to cosmology, the motivation for an " ether theory " is exposed at length; the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Mayeul Arminjon

The problem of the energy-momentum conservation for matter in the gravitational field is discussed on the example of the effective gravity, which arises in superfluids. The "gravitational" field experienced by the relativistic-like massless…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. E. Volovik

Recent high resolution Compton scattering experiments clearly reveal that there are fundamental limitations to the conventional local density approximation (LDA) based description of the ground state electron momentum density (EMD) in…

Strongly Correlated Electrons · Physics 2007-10-11 B. Barbiellini , A. Bansil

The fundamental constants of electromagnetism, gravity and quantum mechanics can be related empirically by the numerical approximation $\ln(V_e/V_P)\approx \alpha^{-1}$, where $\alpha$ is the low energy value of the electromagnetic fine…

General Physics · Physics 2018-01-31 L. Eaves