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Related papers: Nonlocal gravity: Conformally flat spacetimes

200 papers

We explore the cosmological implications of the local limit of nonlocal gravity, which is a classical generalization of Einstein's theory of gravitation within the framework of teleparallelism. An appropriate solution of this theory is the…

General Relativity and Quantum Cosmology · Physics 2024-04-17 Javad Tabatabaei , Abdolali Banihashemi , Shant Baghram , Bahram Mashhoon

We present a covariant study of static space-times, as such and as solutions of gravity theories. By expressing the relevant tensors through the velocity and the acceleration vectors that characterise static space-times, the field equations…

General Relativity and Quantum Cosmology · Physics 2023-09-14 Carlo Alberto Mantica , Luca Guido Molinari

Starting with a field theoretic approach in Minkowski space, the gravitational energy momentum tensor is derived from the Einstein equations in a straightforward manner. This allows to present them as {\it acceleration tensor} = const.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Theo M. Nieuwenhuizen

We continue recent work and formulate the gravitational vacuum Einstein equations over a locally finite spacetime by using the basic axiomatics, techniques, ideas and working philosophy of Abstract Differential Geometry. The whole…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Anastasios Mallios , Ioannis Raptis

Nonlocal gravity (NLG) is a classical nonlocal generalization of Einstein's theory of gravitation developed in close analogy with the nonlocal electrodynamics of media. It appears that the nonlocal aspect of the universal gravitational…

General Relativity and Quantum Cosmology · Physics 2022-09-12 Mahmood Roshan , Bahram Mashhoon

We study the fractional gravity for spacetimes with non-integer dimensions. Our constructions are based on a geometric formalism with the fractional Caputo derivative and integral calculus adapted to nonolonomic distributions. This allows…

Mathematical Physics · Physics 2012-04-20 Sergiu I. Vacaru

The implications of the recent classical nonlocal generalization of Einstein's theory of gravitation for gravitational physics in the Solar System are investigated. In this theory, the nonlocal character of gravity appears to simulate dark…

General Relativity and Quantum Cosmology · Physics 2016-03-23 C. Chicone , B. Mashhoon

This article uses the conformal Einstein equations and the conformal representation of spatial infinity introduced by Friedrich to analyse the behaviour of the gravitational field near null and spatial infinity for the development of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 J. A. Valiente Kroon

The Einstein theories of space-time and gravity as well the stander cosmology are reconstructed thoroughly in this paper based on flat reference frame. The rational parts of the Einstein theories are reserved while the irrational parts…

General Physics · Physics 2007-05-23 Mei Xiaochun

We derive the dynamical equations for a non-local gravity model in the Palatini formalism and we discuss some of the properties of this model. We have shown that, in some specific cases, the vacuum solutions of general relativity are also…

General Relativity and Quantum Cosmology · Physics 2016-12-16 F. Briscese , M. L. Pucheu

In semiclassical gravity the back-reaction of the classical gravitational field interacting with quantum matter fields is described by the semiclassical Einstein equations. A criterion for the validity of semiclassical gravity based on the…

General Relativity and Quantum Cosmology · Physics 2011-08-04 E. Verdaguer

Mathematical modeling of gravitating configurations of physical fields is one of the priority directions of the modern theory of gravity. Most of the exact solutions constructed within the framework of the general relativity are static or…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Ju V Tchemarina , E G Alekseeva , A N Tsirulev , N K Nuraliev

We discuss dynamical aspects of gravitational plane waves in Einstein theory with massless scalar fields. The general analytic solution describes colliding gravitational waves with constant polarization, which interact with scalar waves…

General Relativity and Quantum Cosmology · Physics 2018-10-17 Jorge G. Russo

The Janis-Newman-Winicour metric is a solution of Einstein's gravity minimally coupled to a real massless scalar field. The $\gamma$-metric is instead a vacuum solution of Einstein's gravity. These spacetimes have no horizon and possess a…

General Relativity and Quantum Cosmology · Physics 2018-03-08 Hrishikesh Chakrabarty , Carlos A. Benavides-Gallego , Cosimo Bambi , Leonardo Modesto

A classical nonlocal generalization of Einstein's theory of gravitation has recently been developed via the introduction of a scalar causal "constitutive" kernel that must ultimately be determined from observational data. It turns out that…

Astrophysics of Galaxies · Physics 2014-05-14 S. Rahvar , B. Mashhoon

We prove that the Einstein equations can be solved in a very general form for arbitrary spacetime dimensions and various types of vacuum and non-vacuum cases following a geometric method of anholonomic frame deformations for constructing…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Sergiu I. Vacaru

In particular cases of stationary and stationary axially symmetric space-time passage to non-relativistic limit of Einstein equation is completed. For this end the notions of absolute space and absolute time are introduced due to…

General Relativity and Quantum Cosmology · Physics 2007-06-13 Z. Ya. Turakulov

Among relativistic theories of gravitation the closest ones to general relativity are the scalar-tensor ones and these with Lagrangians being any function f(R) of the curvature scalar. A complete chart of relationships between these…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Leszek M. Sokolowski

We explore some of the cosmological implications of the recent classical nonlocal generalization of Einstein's theory of gravitation in which nonlocality is due to the gravitational memory of past events. In the Newtonian regime of this…

General Relativity and Quantum Cosmology · Physics 2016-08-24 C. Chicone , B. Mashhoon

We solve the Einstein constraint equations for a 3 + 1 dimensional vacuum spacetime with a space-like translational Killing field in the asymptotically flat case.. The presence of a space-like translational Killing field allows for a…

Analysis of PDEs · Mathematics 2014-10-23 Cécile Huneau