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Related papers: Dynamical Masses in Modified Gravity

200 papers

Although general relativity (GR) passes all present experimental tests with flying colors, it remains important to study alternative theories of gravity for several theoretical and phenomenological reasons that we recall in these lecture…

General Relativity and Quantum Cosmology · Physics 2011-02-28 Gilles Esposito-Farese

In this paper we show how the covariant gauge invariant equations for the evolution of scalar, vector and tensor perturbations for a generic $f(R)$-gravity theory can be recast in order to exploit the power of dynamical system methodology.…

Minimally modified gravity is a class of models with only the two tensor degrees of freedom as in general relativity. Using the framework with auxiliary constraints these models can maintain a dynamical cosmological background. The form of…

General Relativity and Quantum Cosmology · Physics 2022-09-02 Alexander Ganz

Strong gravitational lensing by galaxies provides us with a unique opportunity to understand the nature of gravity on galactic and extra-galactic scales. In this paper, we propose a new multimessenger approach using data from both…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-08 Tao Yang , Bin Hu , Rong-Gen Cai , Bin Wang

We consider the effect of a scalar field degree of freedom on the dynamics of gravity from small to large scales. We show that the effects of modified gravity can be completely captured by the time variations of the scalar field mass and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Philippe Brax , Anne-Christine Davis , Baojiu Li

The upcoming Laser Interferometer Space Antenna (LISA) will detect up to thousands of extreme-mass-ratio inspirals (EMRIs). These sources will spend $\sim 10^5$ cycles in band, and are therefore sensitive to tiny changes in the…

General Relativity and Quantum Cosmology · Physics 2026-02-13 Shubham Kejriwal , Enrico Barausse , Alvin J. K. Chua

Many theories of modified gravity, including the well studied Horndeski models, are characterized by a screening mechanism that ensures that standard gravity is recovered near astrophysical bodies. In a recently introduced class of…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Ryo Saito , Daisuke Yamauchi , Shuntaro Mizuno , Jérôme Gleyzes , David Langlois

We investigate gravitational lensing in the Palatini approach to the f(R) extended theories of gravity. Starting from an exact solution of the f(R) field equations, which corresponds to the Schwarzschild-de Sitter metric and, on the basis…

Astrophysics · Physics 2009-07-22 Matteo Luca Ruggiero

In recent years, the modified theory of gravity known as $f(Q)$ gravity has drawn interest as a potential alternative to general relativity. According to this theory, the gravitational force is determined by a function of the so-called…

General Relativity and Quantum Cosmology · Physics 2024-03-13 Pooja Vishwakarma , Parth Shah

We generalize the $f(R)$ type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$ and of the matter Lagrangian $L_m$. We obtain the gravitational field equations in the…

General Relativity and Quantum Cosmology · Physics 2011-02-09 Tiberiu Harko , Francisco S. N. Lobo

We study the effect of $f(R)$ gravity on the statistical properties of various large-scale structures which can be probed in weak gravitational lensing measurements. A set of ray-tracing simulations of gravitational lensing in $f(R)$…

Cosmology and Nongalactic Astrophysics · Physics 2016-05-04 Yuichi Higuchi , Masato Shirasaki

We study fluidized granular gases in a stationary state determined by the balance between an external driving and the bulk dissipation. The two considered situations are inspired by recent experiments, where the gravity plays a major role…

Statistical Mechanics · Physics 2009-10-31 A. Baldassarri , U. Marini Bettolo Marconi , A. Puglisi , A. Vulpiani

We study modifications of general relativity, GR, with nonlinear dispersion relations which can be geometrized on tangent Lorentz bundles. Such modified gravity theories, MGTs, can be modeled by gravitational Lagrange density functionals…

General Physics · Physics 2017-06-13 Panayiotis Stavrinos , Olivia Vacaru , Sergiu I. Vacaru

We discuss the galaxy clustering based on thermodynamics and statistical mechanics in the expanding universe in a modified theory of gravity. The modified general relativity (MGR) is developed using the regular line element field to…

General Physics · Physics 2023-02-15 Abdul W. Khanday , Sudhaker Upadhyay , Prince A. Ganai

We study the dynamical evolution of an $f(R)$ model of gravity in a viscous and anisotropic background which is given by a Bianchi type-I model of the Universe. We find viable forms of $f(R)$ gravity in which one is exactly the Einsteinian…

General Physics · Physics 2014-01-20 Kh. Saaidi , A. Aghamohammadi , H. Hossienkhani

In this contribution one examines the generalization of the $f(R)$ theories of gravity where one introduces a non-minimal coupling between curvature and matter. This model has new and interesting features. %, specially concerning the energy…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Orfeu Bertolami , Miguel Carvalho Sequeira

We review recent progress in the construction of modified gravity models as alternatives to dark energy as well as the development of cosmological tests of gravity. Einstein's theory of General Relativity (GR) has been tested accurately…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-24 Kazuya Koyama

The increasing precision of cosmological data provides us with an opportunity to test general relativity (GR) on the largest accessible scales. Parameterizing modified gravity models facilitates the systematic testing of the predictions of…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-26 Ali Narimani , Douglas Scott

We develop the kinematics in Matrix Gravity, which is a modified theory of gravity obtained by a non-commutative deformation of General Relativity. In this model the usual interpretation of gravity as Riemannian geometry is replaced by a…

General Relativity and Quantum Cosmology · Physics 2011-02-18 Ivan G. Avramidi , Guglielmo Fucci

If it is hypothesised that there is no dark matter then some alternative gravitational theory must take the place of general relativity (GR) on the largest scales. Dynamical measurements can be used to investigate the nature of such a…

Astrophysics · Physics 2008-11-26 Daniel J. Mortlock , Edwin L. Turner