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We give a definition and derive the equations of motion for the center of mass and angular momentum of an axially symmetric, isolated system that emits gravitational and electromagnetic radiation. A central feature of this formulation is…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Carlos N. Kozameh , Gonzalo Quiroga

Motivated by a special consideration in quantum measurement, we present a new improved energy-momentum tensor. The new tensor differs from the traditional canonical and symmetric ones, and can be derived as Nother current from a Lagrangian…

General Relativity and Quantum Cosmology · Physics 2019-03-06 Tao Lei , Zi-Wei Chen , Zhen-Lai Wang , Xiang-Song Chen*

Physicists believe, with some justification, that there should be a correspondence between familiar properties of Newtonian gravity and properties of solutions of the Einstein equations. The Positive Mass Theorem (PMT), first proved over…

Differential Geometry · Mathematics 2007-05-23 Robert Bartnik

Penrose et al. investigated the physical incoherence of the spacetime with negative mass via the bending of light. Precise estimates of time-delay of null geodesics were needed and played a pivotal role in their proof. In this paper, we…

General Relativity and Quantum Cosmology · Physics 2021-06-11 Xiaokai He , Xiaoning Wu , Naqing Xie

We study the dynamics of extended test bodies in flat Friedmann-Robertson-Walker spacetimes. It is shown that such objects can usually alter their inertial mass, spin, and center-of-mass trajectory purely through the use of internal…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Abraham I. Harte

An approximate realistic metric representing the spacetime of neutron stars is obtained by perturbing the Kerr metric. This metric has five parameters, namely the mass, spin or angular momentum, mass quadrupole, spin octupole and mass…

General Relativity and Quantum Cosmology · Physics 2019-09-04 Francisco Frutos-Alfaro

In the present paper we have discussed the mechanics of incompressible test bodies moving in Riemannian spaces with non-trivial curvature tensors. For Hamilton's equations of motion the solutions have been obtained in the parametrical form…

Classical Physics · Physics 2020-12-02 Vasyl Kovalchuk , Barbara Gołubowska , Ewa Eliza Rożko

To the first post-Newtonian order, the gravitational action of mass-energy currents is encoded by the off-diagonal gravitomagnetic components of the spacetime metric tensor. If they are time-dependent, a further acceleration enters the…

General Relativity and Quantum Cosmology · Physics 2024-09-24 Lorenzo Iorio

A general formula is calculated for the connection of a central metric w.r.t.\ a noncommutative spacetime of Lie-algebraic type. This is done by using the framework of linear connections on central bi-modules. The general formula is further…

Mathematical Physics · Physics 2019-09-06 Albert Much , Marcos Rosenbaum , José David Vergara , Diego Vidal-Cruzprieto

We briefly review how to compute the mass and angular momenta of rotating, asymptotically anti-de Sitter spacetimes in Einstein-Gauss-Bonnet theory of gravity using superpotentials derived from standard Noether identities. The calculations…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Nathalie Deruelle

The space rotation invariance hypothesis is examined. The basic space-time properties and the physical object description from this point of view are considered. An $\omega$-invariance as an approximation of the space rotation invariance…

Quantum Physics · Physics 2007-05-23 Andrey V. Novikov-Borodin

When a small, uncharged, compact object is immersed in an external background spacetime, at zeroth order in its mass it moves as a test particle in the background. At linear order, its own gravitational field alters the geometry around it,…

General Relativity and Quantum Cosmology · Physics 2017-06-07 Adam Pound

The paper considers a set of equations describing the static isotropic gravity field of a macroscopic body within the framework of the theory of gravity with a constraint. A general approximate solution of these equations is obtained. The…

General Relativity and Quantum Cosmology · Physics 2024-02-08 Alexander P. Sobolev , Aleksey Sobolev

A metric representing a slowly rotating object with quadrupole moment is obtained using a perturbation method to include rotation into the weak limit of the Erez-Rosen metric. This metric is intended to tackle relativistic astrometry and…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-15 Francisco Frutos-Alfaro , Edwin Retana-Montenegro , Iván Cordero-García , Javier Bonatti González

We consider covariant metric theories of coupled gravity-matter systems satisfying the following two conditions: First, it is assumed that, by a hyperbolic reduction process, a system of first order symmetric hyperbolic partial differential…

General Relativity and Quantum Cosmology · Physics 2009-11-07 I. Racz

The Maxwell equations are formulated on an arbitrary (1+3)-dimensional manifold. Then, imposing a (constrained) linear constitutive relation between electromagnetic field $(E,B)$ and excitation $({\cal D},{\cal H})$, we derive the metric of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Yuri N. Obukhov , Friedrich W. Hehl

The influence of space-time torsion on gravitational interaction at cosmological and astrophysical scales is discussed within the framework of gauge gravitation theory in Riemann-Cartan space-time. It is shown that the interaction of the…

General Relativity and Quantum Cosmology · Physics 2017-09-27 A. V. Minkevich

This paper is a sequence of the work presented in [1], where, the principles of the general relativity have been used to formulate quantum wave equations taking into account the effect of the electromagnetic and strong interactions in the…

General Physics · Physics 2007-05-23 C. C. Barros

The curvature tensor and the scalar curvature are computed in the space of positive definite real matrices endowed by the Kubo-Mori inner product as a Riemannian metric.

Differential Geometry · Mathematics 2007-05-23 Attila Andai , Peter W. Michor , Denes Petz

In a foregoing paper, gravity has been interpreted as the pressure force exerted on matter at the scale of elementary particles by a perfect fluid. Under the condition that Newtonian gravity must be recovered in the incompressible case, a…

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