English
Related papers

Related papers: Extended Theories of Gravity in cosmological and a…

200 papers

The well-formulation and the well-posedness of the Cauchy problem is discussed for {\it hybrid metric-Palatini gravity}, a recently proposed modified gravitational theory consisting of adding to the Einstein-Hilbert Lagrangian an $f(R)$…

General Relativity and Quantum Cosmology · Physics 2014-03-06 Salvatore Capozziello , Tiberiu Harko , Francisco S. N. Lobo , Gonzalo J. Olmo , Stefano Vignolo

In the pursuit of a general formulation for a modified gravitational theory at the non-relativistic level and as an alternative to the dark matter hypothesis, we construct a model valid over a wide variety of astrophysical scales. Through…

Astrophysics of Galaxies · Physics 2011-12-13 S. Mendoza , X. Hernandez , J. C. Hidalgo , T. Bernal

In this study, we investigate a Palatini $f(R)$ gravity model featuring a quadratic term correction, aligning it with the most recent expansion rate data, with a particular focus on the latest SNIa and BAO data. Our analysis employs CC data…

General Relativity and Quantum Cosmology · Physics 2024-01-10 Débora Aguiar Gomes , Rebecca Briffa , Aleksander Kozak , Jackson Levi Said , Margus Saal , Aneta Wojnar

Einstein's General Relativity (GR) is possibly one of the greatest intellectual achievements ever conceived by the human mind. In fact, over the last century, GR has proven to be an extremely successful theory, with a well established…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Tiberiu Harko , Francisco S. N. Lobo

We generalize the known equivalence between higher order gravity theories and scalar tensor theories to a new class of theories. Specifically, in the context of a first order or Palatini variational principle where the metric and connection…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Eanna E. Flanagan

We perform a phase space analysis of a generalized modified gravity theory with nonminimally coupling between geometry and matter. We apply the dynamical system approach to this generalized model and find that in the cosmological context,…

General Relativity and Quantum Cosmology · Physics 2016-05-17 Rui An , Xiaodong Xu , Bin Wang , Yungui Gong

We have derived a modified Lane-Emden equation for the Starobinsky model in Palatini gravity which is numerically solvable. Comparing the results to the ones provided by General Relativity we observe a significant difference depending on…

General Relativity and Quantum Cosmology · Physics 2019-01-23 Aneta Wojnar

We consider the dynamics of tensor and scalar gravitational fields in the Relativistic Theory of Gravitation with the Minkowskian vacuum metric and generalize the formulation to the massless graviton. The potential of scalar field is…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Kiselev

Extended $f(R)$ theories of gravity have been investigated from the symmetry point of view. We briefly has been investigated Noether symmetry of two types of extended $f(R)$ theories: $f(R,T)$ theory, in which curvature is coupled non…

General Relativity and Quantum Cosmology · Physics 2018-10-09 D. Momeni , R. Myrzakulov , E. Güdekli

In this review we present a thoroughly comprehensive survey of recent work on modified theories of gravity and their cosmological consequences. Amongst other things, we cover General Relativity, Scalar-Tensor, Einstein-Aether, and Bimetric…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Timothy Clifton , Pedro G. Ferreira , Antonio Padilla , Constantinos Skordis

The attempt to describe the recent accelerated expansion of the Universe includes different propositions for dark energy models and modified gravity theories. Establish their features in order to discriminate and even rule out part of these…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-01 M. Penna-Lima , S. D. P. Vitenti , M. E. S. Alves , J. C. N. de Araujo , F. C. Carvalho

In this paper, we developed three analytical models and obtained a new class of solutions describing compact stellar structures using the theory of teleparallel gravity. We consider the general anisotropic nature of stellar configurations…

General Relativity and Quantum Cosmology · Physics 2022-09-21 Jay Solanki , Rohan Joshi , Malay Garg

This work investigates alternative theories of gravity, the solutions to their field equations and the constraints that can be imposed upon them from observation and experiment. Specifically, we consider the cosmologies and spherically…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. Clifton

We investigate a non-minimally coupled scalar field theory within the framework of scalar-tensor gravity formulated in non-metricity geometry, focusing on spatially curved FLRW spacetimes. Employing the dynamical systems approach with…

General Relativity and Quantum Cosmology · Physics 2025-09-03 Ghulam Murtaza , Avik De , Andronikos Paliathanasis

In Cuzinatto et al. [Phys. Rev. D 93, 124034 (2016)], it has been demonstrated that theories of gravity in which the Lagrangian includes terms depending on the scalar curvature $R$ and its derivatives up to order $n$, i.e.…

General Relativity and Quantum Cosmology · Physics 2019-05-07 R. R. Cuzinatto , C. A. M. de Melo , L. G. Medeiros , P. J. Pompeia

Scalar-tensor gravity is the simplest and best understood modification of general relativity, consisting of a real scalar field coupled directly to the Ricci scalar curvature. Models of this type have self-accelerating solutions. In an…

Astrophysics · Physics 2009-09-17 Gabriela Barenboim , Joseph Lykken

This paper is devoted to explore modified $f(\mathcal{R})$ theories of gravity using Noether symmetry approach. For this purpose, Friedmann-Robertson-Walker spacetime is chosen to investigate the cosmic evolution. The study is mainly…

General Relativity and Quantum Cosmology · Physics 2020-02-21 M. Farasat Shamir

The discovery of the accelerated expansion of the universe highlighted General Relativity's inability to naturally account for dark energy without invoking a finely tuned cosmological constant. In response, a wide range of alternative…

General Relativity and Quantum Cosmology · Physics 2025-11-11 P. A. G. Monteiro , C. J. A. P. Martins

We revisit the problem of defining non-minimal gravity in the first order formalism. Specializing to scalar-tensor theories, which may be disguised as `higher-derivative' models with the gravitational Lagrangians that depend only on the…

Astrophysics · Physics 2008-11-26 Alberto Iglesias , Nemanja Kaloper , Antonio Padilla , Minjoon Park

We perform a detailed study of the modified gravity $f(R)$ models in the light of the basic geometrical symmetries, namely Lie and Noether point symmetries, which serve to illustrate the phenomenological viability of the modified gravity…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. Paliathanasis , M. Tsamparlis , S. Basilakos