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Related papers: Observational Constraints in Metric-Affine Gravity

200 papers

It is more important than ever to push experimental tests of gravitational theory to the limits of existing technology in both range and sensitivity. This brief review focuses on spin-based tests of General Relativity and their implications…

General Relativity and Quantum Cosmology · Physics 2015-12-09 James M. Overduin

This work provides a short but comprehensible overview of some relevant aspects of metric-affine theories of gravity in relation to the physics and astrophysics of compact objects. We shall highlight the pertinence of this approach to…

General Relativity and Quantum Cosmology · Physics 2020-08-26 Diego Rubiera-Garcia

We consider possible signatures for the so called {\it hybrid gravity} within the Galactic Central Parsec. This modified theory of gravity consists of a superposition of the metric Einstein-Hilbert Lagrangian with an $f(R)$ term constructed…

General Relativity and Quantum Cosmology · Physics 2016-04-20 D. Borka , S. Capozziello , P. Jovanović , V. Borka Jovanović

General Relativity (GR) exists in different formulations, which are equivalent in pure gravity. Once matter is included, however, observable predictions generically depend on the version of GR. In order to quantify the resulting ambiguity,…

General Relativity and Quantum Cosmology · Physics 2024-01-04 Claire Rigouzzo , Sebastian Zell

Solar system observations have traditionally allowed for very stringent tests of Einstein's theory of general relativity. We here revisit the possibility of using these observations to constrain gravitational parity violation as…

General Relativity and Quantum Cosmology · Physics 2019-05-22 Yuya Nakamura , Daiki Kikuchi , Kei Yamada , Hideki Asada , Nicolas Yunes

The aim of our investigation is to derive a particular theory among the class of scalar-tensor(ST) theories of gravity, and then to test it by studying kinematics and dynamics of S-stars around supermassive black hole (BH) at Galactic…

We derive the full set of field equations for the Metric-Affine version of the Myrzakulov gravity model and also extend this family of theories to a broader one. More specifically, we consider theories whose gravitational Lagrangian is…

General Relativity and Quantum Cosmology · Physics 2021-06-10 Damianos Iosifidis , Nurgissa Myrzakulov , Ratbay Myrzakulov

We study the Solar System constraints on covariant $f(Q)$ gravity. The covariant $f(Q)$ theory is described by the metric and affine connection, where both the torsion and curvature vanish. Considering a model including a higher…

General Relativity and Quantum Cosmology · Physics 2024-12-24 Wenyi Wang , Kun Hu , Taishi Katsuragawa

We propose a gravitational model which allows the independent dynamical behaviour of the torsion and nonmetricity fields to be displayed in the framework of Metric-Affine gauge theory of gravity. For this task, we derive a new exact black…

General Relativity and Quantum Cosmology · Physics 2020-10-14 Sebastian Bahamonde , Jorge Gigante Valcarcel

We formulate cosmological perturbation theory around the spatially curved FLRW background in the context of metric-affine gauge theory of gravity which includes torsion and nonmetricity. Performing scalar-vector-tensor decomposition of the…

General Relativity and Quantum Cosmology · Physics 2024-07-18 Katsuki Aoki , Sebastian Bahamonde , Jorge Gigante Valcarcel , Mohammad Ali Gorji

Scalar-tensor theories of gravity can lead to modifications of the gravitational force inside astrophysical objects. We exhibit that compact stars such as white dwarfs provide a unique set-up to test beyond Horndeski theories of ${\rm G}^3$…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-20 Rajeev Kumar Jain , Chris Kouvaris , Niklas Grønlund Nielsen

The spacetime of the metric-affine gauge theory of gravity (MAG) encompasses {\it nonmetricity} and {\it torsion} as post-Riemannian structures. The sources of MAG are the conserved currents of energy-momentum and dilation, shear and spin.…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Yu. N. Obukhov , E. J. Vlachynsky , W. Esser , R. Tresguerres , F. W. Hehl

The GRAVITY Collaboration achieved the remarkable detection of the orbital precession of the S2 star around the Galactic centre supermassive black hole, providing yet another proof of the validity of the General Relativity. The departure…

General Relativity and Quantum Cosmology · Physics 2021-11-18 Ivan de Martino , Riccardo della Monica , Mariafelicia de Laurentis

This thesis covers several developments performed in metric-affine gravity. This alternative framework extends General Relativity by considering a more general connection than the one induced by the metric (i.e., arbitrary torsion and…

General Relativity and Quantum Cosmology · Physics 2022-02-01 Alejandro Jiménez-Cano

We consider metric-affine scenarios where a modified gravitational action is sourced by electrovacuum fields in a three dimensional space-time. Such scenarios are supported by the physics of crystalline structures with microscopic defects…

General Relativity and Quantum Cosmology · Physics 2015-08-13 Cosimo Bambi , M. Ghasemi-Nodehi , D. Rubiera-Garcia

This paper is the third in a series on tests of gravity using observations of stars and nearby dwarf galaxies. We carry out four distinct tests using published data on the kinematics and morphology of dwarf galaxies, motivated by the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Vinu Vikram , Anna Cabre , Bhuvnesh Jain , Jake VanderPlas

We investigate the possibility to explain theoretically the observed deviations of S2 star orbit around the Galactic Centre using gravitational potentials derived from modified gravity models in absence of dark matter. To this aim, an…

Astrophysics of Galaxies · Physics 2016-08-10 S. Capozziello , D. Borka , P. Jovanović , V. Borka Jovanović

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

We give a self-contained introduction into the metric-affine gauge theory of gravity. Starting from the equivalence of reference frames, the prototype of a gauge theory is presented and illustrated by the example of Yang-Mills theory. Along…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Frank Gronwald

The coupling of the electromagnetic field directly with gravitational gauge fields leads to new physical effects that can be tested using astronomical data. Here we consider a particular case for closer scrutiny, a specific nonminimal…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Oliver Preuss , Mark P. Haugan , Sami K. Solanki , Stefan Jordan
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