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Related papers: Solar system constraints on f(G) gravity models

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We present current and future constraints on the Hu and Sawicki modified gravity scenario. This model can reproduce a late time accelerated universe and evade solar system constraints. While current cosmological data still allows for…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Matteo Martinelli , Alessandro Melchiorri , Olga Mena , Valentina Salvatelli , Zahara Girones

We investigate an ability of the exponential power-law inflation to be phenomenologically correct model of the early universe. GR scalar cosmology equations we study in Ivanov-Salopek-Bond (or Hamilton-Jacobi like) representation where the…

General Relativity and Quantum Cosmology · Physics 2025-01-22 I. V. Fomin , S. V. Chervon

The field equations of Mannheim's theory of conformal gravity with dynamic mass generation are solved numerically in the interior and exterior regions of a model spherically symmetric sun with matched boundary conditions at the surface. The…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Joshua Wood , William Moreau

We explore the cosmological dynamics of a teleparallel Gauss-Bonnet gravity model defined by the torsion scalar $T$ and the torsion-based Gauss-Bonnet invariant $T_{\mathcal{G}}$, deriving modified Friedmann equations for a flat FLRW…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Santosh V. Lohakare , S. K. Maurya , Aaisha Al Qassabi , B. Mishra

We study stellar configurations and the space-time around them in metric $f(R)$ theories of gravity. In particular, we focus on the polytropic model of the Sun in the $f(R)=R-\mu^4/R$ model. We show how the stellar configuration in the…

Astrophysics · Physics 2008-12-18 K. Henttunen , T. Multamaki , I. Vilja

Disformal theories of gravity are scalar-tensor theories where the scalar couples derivatively to matter via the Jordan frame metric. These models have recently attracted interest in the cosmological context since they admit accelerating…

General Relativity and Quantum Cosmology · Physics 2015-11-04 Hiu Yan Ip , Jeremy Sakstein , Fabian Schmidt

New corrections to General Relativity are considered in the context of modified $f(R)$ gravity, that satisfy cosmological and local gravity constraints. The proposed models behave asymptotically as $R-2\Lambda$ at large curvature and show…

General Relativity and Quantum Cosmology · Physics 2022-01-13 L. N. Granda

A class of well-behaved modified gravity models with long enough matter domination epoch and a late-time accelerated expansion is confronted with SNIa, CMB, SDSS, BAO and H(z) galaxy ages data, as well as current measurements of the linear…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-09 Z. Girones , A. Marchetti , O. Mena , C. Pena-Garay , N. Rius

We present a novel approach to modified theories of gravity that consists of adding to the Einstein-Hilbert Lagrangian an f(R) term constructed a la Palatini. Using the respective dynamically equivalent scalar-tensor representation, we show…

General Relativity and Quantum Cosmology · Physics 2012-04-26 Tiberiu Harko , Tomi S. Koivisto , Francisco S. N. Lobo , Gonzalo J. Olmo

A cosmological model with a specific form of the Hubble parameter is constructed in a flat homogeneous, and isotropic background in the framework of $f(R, T)$ gravity, where $R$ is the scalar curvature and $T$ is the trace of the…

General Relativity and Quantum Cosmology · Physics 2018-07-04 J. K. Singh , Kazuharu Bamba , Ritika Nagpal , S. K. J. Pacif

We have assumed the FRW model of the universe in Galileon gravity, which is filled with dark matter and Modified Chaplygin gas (MCG) type dark energy. We present the Hubble parameter in terms of some unknown parameters and observational…

General Physics · Physics 2015-06-19 Chayan Ranjit , Prabir Rudra , Ujjal Debnath

Since general relativity is the unique theory of massless spin 2 particles at large distances, the most reasonable way to have significant modifications is to introduce one or more light scalars that mediate a new long-range force. Most…

High Energy Physics - Theory · Physics 2023-02-02 Mark P. Hertzberg , Jacob A. Litterer , Neil Shah

Models of modified gravity offer promising alternatives to the concordance $\Lambda$CDM cosmology to explain the late-time acceleration of the universe. A popular such model is $f(R)$ gravity, in which the Ricci scalar in the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-14 Christine Corbett Moran , Romain Teyssier , Baojiu Li

The article investigates cosmological applications of $f(Q)$ theories in a non-coincident formalism. We explore a new $f(Q)$ theory dynamics utilizing a non-vanishing affine connection involving a non-constant function…

General Relativity and Quantum Cosmology · Physics 2024-10-03 Sneha Pradhan , Raja Solanki , P. K. Sahoo

The study of modified gravity models has garnered significant attention because of their potential to provide alternative explanations for cosmological phenomena, such as the accelerated expansion of the universe and the nature of dark…

General Relativity and Quantum Cosmology · Physics 2025-05-27 Davood Momeni , Ratbay Myrzakulov

The post Newtonian parameter is considered in the Chameleon-Brans-Dicke frame. In the first step, the general form of this parameter and also effective gravitational constant is obtained. An arbitrary function for $f(\Phi)$, which indicates…

General Relativity and Quantum Cosmology · Physics 2014-01-20 Khaled Saaidi , Abolhassan Mohammadi , Haidar Sheikhahmadi

Experiments on the violation of equivalence principle (EP) and solar system give a number of constraints in which any modified gravity model must satisfy them. We study these constraints on a kind of $f(R)$ gravity as $f(R) = R(1\pm…

General Relativity and Quantum Cosmology · Physics 2014-01-20 Kh. Saaidi , A. Aghamohammadi

We study the motion of particles in the background of a scalar-tensor theory of gravity in which the scalar field is kinetically coupled to Einstein tensor. We constrain the value of the derivative parameter $z$ through solar system tests.…

General Relativity and Quantum Cosmology · Physics 2020-12-02 P. A. González , Marco Olivares , Eleftherios Papantonopoulos , Yerko Vásquez

All $f(R)$ modified gravity theories are conformally identical to models of quintessence in which matter is coupled to dark energy with a strong coupling. This coupling induces a cosmological evolution radically different from standard…

Astrophysics · Physics 2008-11-26 Luca Amendola , David Polarski , Shinji Tsujikawa

In this paper, we present an accelerating cosmological model by constraining the free parameters using the cosmological datasets in an extended symmetric teleparallel gravity for the flat and anisotropic space-time. We employ a time…

General Relativity and Quantum Cosmology · Physics 2023-06-27 S. A. Narawade , M. Koussour , B. Mishra
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