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Related papers: Affine theory of gravitation

200 papers

The role of torsion in f(R) gravity is considered in the framework of metric-affine formalism. We discuss the field equations in empty space and in presence of perfect fluid matter taking into account the analogy with the Palatini…

General Relativity and Quantum Cosmology · Physics 2008-11-26 S. Capozziello , R. Cianci , C. Stornaiolo , S. Vignolo

We study a cosmological model based on the canonical Hamiltonian transformation theory. Using a linear-quadratic approach for the free gravitational De Donder-Weyl Hamiltonian $H_\mathrm{Gr}$, the model contains terms describing a…

General Relativity and Quantum Cosmology · Physics 2023-06-07 Johannes Kirsch , David Vasak , Armin van de Venn , Jürgen Struckmeier

The Polynomial Affine Gravity is an alternative gravitational model, where the interactions are mediated solely by the affine connection, instead of the metric tensor. In this paper, we explore the space of solutions to the field equations…

General Relativity and Quantum Cosmology · Physics 2024-06-05 Oscar Castillo-Felisola , Bastian Grez , Gonzalo J. Olmo , Oscar Orellana , José Perdiguero Gárate

We generalize tensor-scalar theories of gravitation by the introduction of an abnormally weighting type of energy. This theory of tensor-scalar anomalous gravity is based on a relaxation of the weak equivalence principle that is now…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 J. -M. Alimi , A. Fuzfa

The theory of Gravitomagnetism and spinor quantum mechanics describing the interaction between the Dirac spinor field, the electromagnetic field, and a weak gravitational field is extended by including the Lagrangian density of the free…

General Relativity and Quantum Cosmology · Physics 2024-02-15 Dalibor Javůrek

We shall give dynamics to our spacetime manifold by first identifying the local affine symmetry as the characterizing symmetry for our geometry a'la Felix Klein, this symmetry is imposed on us by the Law of Inertia and the Law of Causality.…

General Physics · Physics 2013-12-18 Yi Yang , Wai Bong Yeung

Recently, a new alternative vector theory of gravity has been proposed which assumes that universe has fixed background Euclidean geometry and gravity is a vector field that alters this geometry [Phys. Scr. 92, 125001 (2017)]. It has been…

General Physics · Physics 2019-05-28 Anatoly A. Svidzinsky

We generalize the basic theory of mimetic gravity by extending its purview to the general metric-compatible geometries that admit torsion, in addition to curvature. This essentially implies reinstating the mimetic principle of isolating the…

General Relativity and Quantum Cosmology · Physics 2025-04-02 Hiyang Ramo Chothe , Ashim Dutta , Sourav Sur

We present the theory of weak gravitational lensing in cosmologies with generalized gravity, described in the Lagrangian by a generic function depending on the Ricci scalar and a non-minimally coupled scalar field. We work out the…

Astrophysics · Physics 2009-11-10 Viviana Acquaviva , Carlo Baccigalupi , Francesca Perrotta

The equations of motion for matter fields are invariant under the shift of the matter lagrangian by a constant. Such a shift changes the energy momentum tensor of matter by T^a_b --> T^a_b +\rho \delta^a_b. In the conventional approach,…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. Padmanabhan

Starting from the action function, we have derived a theoretical background that leads to the quantization of gravity and the deduction of a correlation between the gravitational and the inertial masses, which depends on the kinetic…

General Physics · Physics 2014-02-18 Fran De Aquino

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

The fundamental interactions of nature, the electroweak and the quantum chromodynamics, are described in the Standard Model by the Gauge Theory under internal symmetries that maintain the invariance of the functional action. The fundamental…

General Relativity and Quantum Cosmology · Physics 2019-05-21 Wytler Cordeiro dos Santos

The relativistic theory of gravitation has the considerable difficulties by description of the gravitational field energy. Pseudotensor t00 in the some cases cannot be interpreted as energy density of the gravitational field. In [1] the…

General Relativity and Quantum Cosmology · Physics 2007-06-22 Roald Sosnovskiy

We consider the sum of the Einstein-Hilbert action and a Pontryagin density (PD) in arbitrary even dimension $D$. All curvatures are functions of independent affine (torsionless) connections only. In arbitrary dimension, not only in $D=4n$,…

General Relativity and Quantum Cosmology · Physics 2022-12-12 Ulf Lindström , Özgür Sarıoğlu

The cosmological constant is not an absolute constant. The gravitating part of the vacuum energy is adjusted to the energy density of matter and to other types of the perturbations of the vacuum. We discuss how the vacuum energy responds…

General Relativity and Quantum Cosmology · Physics 2007-05-23 G. E. Volovik

One of the main features of unified models, based on affine geometries, is that all possible interactions and fields naturally arise under the same standard. Here, we consider, from the effective Lagrangian of the theory, the torsion…

High Energy Physics - Theory · Physics 2014-04-09 Diego Julio Cirilo-Lombardo , Salvatore Capozziello , Alexander Dorokhov

We derive the exact gravitational wave solutions in a general class of quadratic metric-affine gauge gravity models. The Lagrangian includes all possible linear and quadratic invariants constructed from the torsion, nonmetricity and the…

General Relativity and Quantum Cosmology · Physics 2021-01-14 Alejandro Jiménez-Cano , Yuri N. Obukhov

The so-called $\Gamma\Gamma$-form of the gravitational Lagrangian, long known to provide its most compact expression as well as the most efficient generation of the graviton vertices, is taken as the starting point for discussing General…

High Energy Physics - Theory · Physics 2017-10-25 E. T. Tomboulis

A modified gravitational theory explains early universe and late time cosmology, galaxy and galaxy cluster dynamics. The modified gravity (MOG) theory extends general relativity (GR) by three extra degrees of freedom: a scalar field $G$,…

General Relativity and Quantum Cosmology · Physics 2020-10-30 J. W. Moffat
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