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Related papers: Einstein-Riemann Gravity on Deformed Spaces

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Motivated by conventional gauge theories, we consider a theory of gravity in which the Einstein-Hilbert action is replaced by a term that is quadratic in the Riemann tensor. We focus on cosmological solutions to the field equations in flat,…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. N. Lasenby , C. J. L. Doran , R. Heineke

Starting from gravity as a Chern-Simons action for the AdS algebra in five dimensions, it is possible to deform the theory through an expansion of the Lie algebra that leads to a system consisting of the Einstein-Hilbert action plus…

High Energy Physics - Theory · Physics 2016-08-16 José D. Edelstein , Mokhtar Hassaïne , Ricardo Troncoso , Jorge Zanelli

In contrast to electrodynamics, Einstein's gravitation equations are not invariant with respect to a wide class of the mapping of field variables which leave equations of motion of test particles in a given coordinate system invariant. It…

General Relativity and Quantum Cosmology · Physics 2008-05-20 Leonid Verozub

Noncommutative (NC) gravity is constructed on the canonical noncommutative (Moyal-Weyl) space-time as a noncommutative $SO(2,3)_\star$ gauge theory. The NC gravity action consists of three different terms: the first term is of Mac-Dowell…

High Energy Physics - Theory · Physics 2017-09-27 Marija Dimitrijević Ćirić , Biljana Nikolić , Voja Radovanović

We summarise recent perspectives on symmetries of noncommutative field theories based on homotopy algebras. We show how these viewpoints naturally lead to a new class of noncommutative field theories which possess braided gauge symmetries,…

High Energy Physics - Theory · Physics 2022-04-01 Richard J. Szabo

Starting from a self-dual formulation of gravity, we obtain a noncommutative theory of pure Einstein theory in four dimensions. In order to do that, we use Seiberg-Witten map. It is shown that the noncommutative torsion constraint is solved…

High Energy Physics - Theory · Physics 2009-11-10 H. Garcia-Compean , O. Obregon , C. Ramirez , M. Sabido

In the Hamiltonian formulation of general relativity, Einstein's equation is replaced by a set of four constraints. Classically, the constraints can be identified with the generators of the hypersurface-deformation Lie algebroid (HDA) that…

High Energy Physics - Theory · Physics 2018-08-08 Martin Bojowald , Suddhasattwa Brahma , Umut Buyukcam , Michele Ronco

Deformed special relativity is embedded in deformed general relativity using the methods of canonical relativity and loop quantum gravity. Phase-space dependent deformations of symmetry algebras then appear, which in some regimes can be…

General Relativity and Quantum Cosmology · Physics 2013-08-05 Martin Bojowald , George M. Paily

We construct invariant differential operators acting on sections of vector bundles of densities over a smooth manifold without using a Riemannian metric. The spectral invariants of such operators are invariant under both the diffeomorphisms…

High Energy Physics - Theory · Physics 2009-11-10 Ivan G. Avramidi

We study the problem of reality in the geometric formalism of the 4D noncommutative gravity using the known deformation of the diffeomorphism group induced by the twist operator with the constant deformation parameters $\vt^{mn}$. It is…

High Energy Physics - Theory · Physics 2016-04-26 B. M. Zupnik

The Einstein-Hilbert action in three dimensions and the transformation rules for the dreibein and spin connection can be naturally described in terms of gauge theory. In this spirit, we use covariant coordinates in noncommutative gauge…

We construct explicitly deformations of Einstein's theory of gravity that are consistent and phenomenologically viable since they respect, in particular, cosmological backgrounds. We show that these deformations have unique symmetries in…

High Energy Physics - Theory · Physics 2013-05-30 Felix Berkhahn , Dennis Dietrich , Stefan Hofmann , Florian Kühnel , Parvin Moyassari

We put forward the idea that in addition to diffeomorphism invariance of general relativity (GR) the gravitational interaction is invariant under arbitrary scale-deformations of the metric field. In addition, we assume that the scaling…

General Relativity and Quantum Cosmology · Physics 2022-05-19 Meir Shimon

Gravitational probes should maintain spatial flatness for Einsten-Infeld-Hoffmann dynamics of relativistic matter-energy. The continuous elementary source/particle in Einstein's gravitational theory is the r^{-4} radial energy density…

General Physics · Physics 2008-10-10 I. E. Bulyzhenkov

We develop an approach to the theory nonholonomic relativistic stochastic processes on curved spaces. The Ito and Stratonovich calculus are formulated for spaces with conventional horizontal (holonomic) and vertical (nonholonomic) splitting…

Mathematical Physics · Physics 2012-03-27 Sergiu I. Vacaru

The configuration space of general relativity is superspace - the space of all Riemannian 3-metrics modulo diffeomorphisms. However, it has been argued that the configuration space for gravity should be conformal superspace - the space of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Bryan Kelleher

A calculation by Jacobson [1] strongly implies that the field equations which describe gravity are emergent phenomena. In this paper, the method is extended to the case of a non-commutative spacetime. By making use of a non-commutative…

High Energy Physics - Theory · Physics 2015-05-21 Simon Moolman

In this work, we show that a class of metric-affine gravities can be reduced to a Riemann-Cartan one. The reduction is based on the cancelation of the nonmetricity against the symmetric components of the spin connection. A heuristic proof,…

High Energy Physics - Theory · Physics 2010-12-17 R. F. Sobreiro , V. J. Vasquez Otoya

The evolution of a generally covariant theory is under-determined. One hundred years ago such dynamics had never before been considered; its ramifications were perplexing, its future important role for all the fundamental interactions under…

General Relativity and Quantum Cosmology · Physics 2016-11-23 James M. Nester , Chiang-Mei Chen

The gravitational interaction, as described by the Einstein-Cartan theory, is shown to emerge as the by-product of the spontaneous symmetry breaking of a gauge symmetry in a pre-geometric four-dimensional spacetime. Starting from a…

High Energy Physics - Theory · Physics 2025-01-15 Andrea Addazi , Salvatore Capozziello , Antonino Marciano , Giuseppe Meluccio