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Related papers: Nonlocal gravity: Conformally flat spacetimes

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Following the formalism of enveloping algebras and star product calculus we formulate and analyze a model of gauge gravity on noncommutative spaces and examine the conditions of its equivalence to general relativity. The corresponding…

High Energy Physics - Theory · Physics 2014-11-18 Sergiu I. Vacaru

We present a set of three PDEs for three real scalars that are equivalent to the full Einstein equations without any symmetry assumptions. The main variables in this formulation are null surfaces and a conformal factor. Furthermore, for…

General Relativity and Quantum Cosmology · Physics 2012-01-17 Melina Bordcoch , Carlos Kozameh , Alejandra Rojas

In a previous work, it was shown that all Ricci-flat spacetimes are exact solutions for a large class of non-local gravitational theories. Here we prove that, for a subclass of non-local theories, the Schwarzschild singularity is stable…

General Relativity and Quantum Cosmology · Physics 2017-09-20 Gianluca Calcagni , Leonardo Modesto

There are a number of publications on relativistic objects dealing either with black holes or naked singularities in the center. Here we show that there exist static spherically symmetric solutions of Einstein equations with a strongly…

General Relativity and Quantum Cosmology · Physics 2024-08-27 O. S. Stashko , V. I. Zhdanov

To study asymptotic structures, we regularize Einstein's field equations by means of conformal transformations. The conformal factor is chosen so that it carries a dimensional scale that captures crucial asymptotic features. By choosing a…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Niklas Rohr , Claes Uggla

We give here a list of exact classical solutions of a large class of weakly nonlocal theories of gravity, which are unitary and super-renormalizable (or finite) at quantum level. It is explicitly shown that flat and Ricci-flat spacetimes as…

High Energy Physics - Theory · Physics 2016-01-27 Yao-Dong Li , Leonardo Modesto , Leslaw Rachwal

Generalized symmetries of the Einstein equations are infinitesimal transformations of the spacetime metric that formally map solutions of the Einstein equations to other solutions. The infinitesimal generators of these symmetries are…

General Relativity and Quantum Cosmology · Physics 2009-10-22 C. G. Torre , I. M. Anderson

We formulate an approach to the geometry of Riemann-Cartan spaces provided with nonholonomic distributions defined by generic off-diagonal and nonsymmetric metrics inducing effective nonlinear and affine connections. Such geometries can be…

General Relativity and Quantum Cosmology · Physics 2008-12-19 Sergiu I. Vacaru

We investigate a possible unified theory of all interactions which is based only on fundamental spinor fields. The vielbein and metric arise as composite objects. The effective quantum gravitational theory can lead to a modification of…

High Energy Physics - Theory · Physics 2009-11-10 C. Wetterich

In this talk, I present a theory of quantum gravity beyond Einstein. The theory is established based on spinnic and scaling gauge symmetries by treating the gravitational force on the same footing as the electroweak and strong forces. A…

High Energy Physics - Theory · Physics 2015-11-04 Yue-Liang Wu

We present a class of conformally flat solutions of the Einstein's field equations for spherical systems undergoing gravitational collapse accompanied with radial heat flux. The interior space-time of the collapsing matter is chosen to be…

General Relativity and Quantum Cosmology · Physics 2017-11-20 Ranjan Sharma , Shyam Das , Ramesh Tikekar

This work places the invariant $ds^2$ at the center of the gravitational interaction, interpreting it not as a purely geometric object but as the differential of proper time, endowed with direct physical meaning. Starting from the extension…

General Relativity and Quantum Cosmology · Physics 2026-03-10 Jaume de Haro

All global solutions of arbitrary topology of the most general 1+1 dimensional dilaton gravity models are obtained. We show that for a generic model there are globally smooth solutions on any non-compact 2-surface. The solution space is…

High Energy Physics - Theory · Physics 2016-09-06 T. Kloesch , T. Strobl

Gravitation, according to General Relativity, is an attribute of space-time's geometry and hence not a force in the Newtonian sense. This is a consequence of Einstein's equivalence principle, which so far passed all experimental tests with…

Popular Physics · Physics 2013-09-10 Domenico Giulini

In this work, we study linearised gravitational fields on the entire Minkowski space-time including space-like infinity. The generalised conformal field equations linearised about a Minkowski background are utilised for this purpose. In…

General Relativity and Quantum Cosmology · Physics 2017-02-08 Georgios Doulis , Jörg Frauendiener

We study a model for gravity in 3+1 dimensions, inspired in general relativity in 2+1 dimensions. In contrast regular general relativity in 3+1 dimensions, the model postulates that space in absence of matter is flat. The requirement that…

General Relativity and Quantum Cosmology · Physics 2011-11-29 Maarten van de Meent

It is shown explicitly that in the framework of Bohmian quantum gravity, the equations of motion of the space-time metric are Einstein's equations plus some quantum corrections. It is observed that these corrections are not covariant. So…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Ali Shojai , Fatimah Shojai , Mehdi Golshani

We propose a nonlocal scalar-tensor model of gravity with pseudodifferential operators inspired by the effective action of p-adic string and string field theory on flat spacetime. An infinite number of derivatives act both on the metric and…

High Energy Physics - Theory · Physics 2010-12-28 Gianluca Calcagni , Giuseppe Nardelli

We analyze the structure of a recent nonlocal generalization of Einstein's theory of gravitation by Mashhoon et al. By means of a covariant technique, we derive an expanded version of the nonlocality tensor which constitutes the theory. At…

General Relativity and Quantum Cosmology · Physics 2019-05-10 Dirk Puetzfeld , Yuri N. Obukhov , Friedrich W. Hehl

We investigate the conformal geometry of spherically symmetric spacetimes in general without specifying the form of the matter distribution. The general conformal Killing symmetry is obtained subject to a number of integrability conditions.…

General Relativity and Quantum Cosmology · Physics 2016-11-15 S. Moopanar , S. D. Maharaj
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