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Related papers: Effectively nonlocal metric-affine gravity

200 papers

We construct new explicit vacuum solutions of quadratic metric-affine gravity. The approach of metric-affine gravity in using an independent affine connection produces a theory with 10+64 unknowns, which implies admitting torsion and…

General Relativity and Quantum Cosmology · Physics 2019-02-27 Vedad Pasic , Elvis Barakovic

In this paper, we first review some aspects of the f(R) gravity and then the concept of torsion of space-time due to metric-affine formalism in f(R) gravity is studied. Within this formalism in which the matter action is supposed to…

General Physics · Physics 2012-07-10 Majid Mohsenzadeh , Ebrahim Yusofi

A nonlocal generalization of Einstein's theory of gravitation is constructed within the framework of the translational gauge theory of gravity. In the linear approximation, the nonlocal theory can be interpreted as linearized general…

General Relativity and Quantum Cosmology · Physics 2009-03-24 Friedrich W. Hehl , Bahram Mashhoon

Despite many nice properties and numerous achievements, general relativity is not a complete theory. One of actual approaches towards more complete theory of gravity is its nonlocal modification. We present here a brief review of nonlocal…

General Relativity and Quantum Cosmology · Physics 2017-01-04 Branko Dragovich

Like general relativity, metric-affine gravity should be a viable effective quantum theory, otherwise it is a mathematical curiosity without physical application. Assuming a perturbative quantum field theory, the universal, flat limit of…

High Energy Physics - Theory · Physics 2025-11-18 Will Barker , Carlo Marzo , Alessandro Santoni

We briefly review ideas about ``noncommutativity of space-time'' and approaches toward a corresponding theory of gravity.

General Relativity and Quantum Cosmology · Physics 2008-11-26 Folkert Muller-Hoissen

The possibility of the extension of spatial diffeomorphisms to a larger family of symmetries in a class of classical field theories is studied. The generator of the additional local symmetry contains a quadratic kinetic term and a potential…

High Energy Physics - Theory · Physics 2015-05-18 Szilard Farkas , Emil J. Martinec

Within the theory of the ghost-free bigravity, we present the most general cosmological solution for which the physical metric is homogeneous and isotropic, while the second metric is inhomogeneous. The solution includes a matter source and…

High Energy Physics - Theory · Physics 2015-06-05 Mikhail S. Volkov

We argue that quantum gravity is nonlocal, first by recalling well-known arguments that support this idea and then by focusing on a point not usually emphasized: that making a conventional effective field theory (EFT) for quantum gravity is…

High Energy Physics - Theory · Physics 2022-01-26 Nicolás Valdés-Meller

The ghost-free bimetric theory describes interactions of gravity with another spin-2 field in terms of two Lorentzian metrics. However, if the two metrics do not admit compatible notions of space and time, the formulation of the initial…

High Energy Physics - Theory · Physics 2018-06-13 S. F. Hassan , Mikica Kocic

We provide a systematic and updated discussion of a research line carried out by our group over the last few years, in which gravity is modified at cosmological distances by the introduction of nonlocal terms, assumed to emerge at an…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Enis Belgacem , Yves Dirian , Andreas Finke , Stefano Foffa , Michele Maggiore

We consider nonlocal modification of the Einstein theory of gravity in framework of the pseudo-Riemannian geometry. The nonlocal term has the form $\mathcal{H}(R) \mathcal{F}(\Box)\mathcal {G}(R)$, where $\mathcal{H}$ and $\mathcal{G}$ are…

High Energy Physics - Theory · Physics 2015-08-25 Ivan Dimitrijevic , Branko Dragovich , Jelena Grujic , Zoran Rakic

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

We investigate Extended Geometric Trinity of Gravity at both classical and quantum cosmological levels using the minisuperspace approach. Adopting Noether symmetries to select viable models, we examine metric-affine theories of gravity, in…

General Relativity and Quantum Cosmology · Physics 2026-03-24 Emmanuele Battista , Salvatore Capozziello , Stefano Pastore

In a talk at the conference {\it Geometrical Foundations of Gravity at Tartu 2017}, it was suggested that the affine spacetime connection could be associated with purely fictitious forces. This leads to gravitation in a flat and smooth…

General Relativity and Quantum Cosmology · Physics 2018-09-13 Tomi Koivisto

In this paper we review the Myrzakulov Gravity models (MG-N, with $\mathrm{N = I, II, \ldots, VIII}$) and derive their respective metric-affine generalizations (MAMG-N), discussing also their particular sub-cases. The field equations of the…

General Relativity and Quantum Cosmology · Physics 2021-11-03 N. Myrzakulov , R. Myrzakulov , L. Ravera

Torsion and curvature could play a fundamental role in explaining cosmological dynamics. f(R)-gravity with torsion is an approach aimed to encompass in a comprehensive scheme all the Dark Side of the Universe (Dark Energy and Dark Matter).…

General Relativity and Quantum Cosmology · Physics 2014-11-20 S. Capozziello , S. Vignolo

We develop the method of anholonomic frames with associated nonlinear connection (in brief, N--connection) structure and show explicitly how geometries with local anisotropy (various type of Finsler--Lagrange--Cartan--Hamilton geometry) can…

High Energy Physics - Theory · Physics 2007-05-23 Sergiu I. Vacaru

Current generalizations of the classical Einstein-Hilbert Lagrangian formulation of General Relativity are reviewed. Some alternative variational principles are known to reproduce Einstein's gravitational equations, and should therefore be…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Guido Magnano

Modified theories of gravity have been invoked recently as an alternative to dark energy, in an attempt to explain the apparent accelerated expansion of the universe at the present time. In order to describe inhomogeneities in cosmological…

General Relativity and Quantum Cosmology · Physics 2016-04-15 Adam J. Christopherson