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Related papers: Astrophysical Tests of Screened Modified Gravity

200 papers

Scalar fields are crucial components in high energy physics and extensions of General Relativity. The fact they are not observed in the solar system may be due to a mechanism which screens their presence in high dense regions. We show how…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-04 Claudio Llinares , David F. Mota

After a decade and a half of research motivated by the accelerating universe, theory and experiment have a reached a certain level of maturity. The development of theoretical models beyond \Lambda, or smooth dark energy, often called…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-25 Austin Joyce , Bhuvnesh Jain , Justin Khoury , Mark Trodden

Fifth forces are ubiquitous in modified gravity theories, and must be screened to evade stringent local tests. This can introduce unusual behaviour in galaxy phenomenology by affecting galaxies' components differently. Here we use the…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-18 Ricardo G. Landim , Harry Desmond , Kazuya Koyama , Samantha Penny

We review recent developments and results in testing general relativity (GR) at cosmological scales. The subject has witnessed rapid growth during the last two decades with the aim of addressing the question of cosmic acceleration and the…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-09 Mustapha Ishak

The screened modified gravity (SMG) is a unified theoretical framework, which describes the scalar-tensor gravity with screening mechanism. Based on the gravitational-wave (GW) waveform derived in our previous work \citep{liu2018waveforms},…

General Relativity and Quantum Cosmology · Physics 2020-02-28 Rui Niu , Xing Zhang , Tan Liu , Jiming Yu , Bo Wang , Wen Zhao

Despite its remarkable agreement with gravity tests in the solar system, general relativity is challenged at larger scales. Large scale tests performed in the solar system by the Pioneer 10/11 probes have failed to confirm the expected…

General Relativity and Quantum Cosmology · Physics 2008-06-17 Marc-Thierry Jaekel , Serge Reynaud

We propose a new method to test modified gravity theories, taking advantage of the available data on extrasolar planets. We computed the deviations from the Kepler third law and use that to constrain gravity theories beyond General…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-26 Marcelo Vargas dos Santos , David F. Mota

We explore the possibility of testing modified gravity exhibiting the Vainshtein mechanism against observations of cluster lensing. We work in the most general scalar-tensor theory with second-order field equations (Horndeski's theory), and…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-14 Tatsuya Narikawa , Tsutomu Kobayashi , Daisuke Yamauchi , Ryo Saito

In this work we present a brief discussion about modified and extended cosmological models using current observational tests. We show that according to these astrophysical samples based in late universe measurements, theories like $f(R)$…

General Relativity and Quantum Cosmology · Physics 2021-01-25 Celia Escamilla-Rivera

Extending general relativity by adding extra degrees of freedom is a popular approach for explaining the accelerated expansion of the Universe and to build high energy completions of the theory of gravity. The presence of such new degrees…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 R. Hagala , C. Llinares , D. F. Mota

In the past few decades, various versions of modified gravity theories were proposed to mimic the effect of dark matter. Compared with the conventional Newtonian or relativistic dynamics, these theories contain some extra apparent force…

General Relativity and Quantum Cosmology · Physics 2023-02-01 Man Ho Chan , Chak Man Lee

We describe here how planetary ephemerides are built in the framework of General Relativity and how they can be used to test alternative theories. We focus on the definition of the reference frame (space and time) in which the planetary…

General Relativity and Quantum Cosmology · Physics 2024-07-25 Agnès Fienga , Olivier Minazzoli

Cosmological observations are beginning to reach a level of precision that allow us to test some of the most fundamental assumptions in our working model of the Universe. One such an assumption is that gravity is governed by the General…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-11 Pedro G. Ferreira

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 analyze cosmography as a tool to constrain modified gravity theories. We take four distinct models and obtain their parameters in terms of the cosmographic parameters favored by observational data of strong gravitational lensing. We…

General Relativity and Quantum Cosmology · Physics 2025-02-06 Mario H. Amante , Andrés Lizardo , Javier Chagoya , C. Ortiz

We use cosmological hydrodynamical simulations to study the effect of screened modified gravity models on the mass estimates of galaxy clusters. In particular, we focus on two novel aspects: (i) we study modified gravity models in which…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Max Gronke , A. Hammami , David F. Mota , Hans A. Winther

Theories that attempt to explain cosmic acceleration by modifying gravity typically introduces a long-range scalar force that needs to be screened on small scales. One common screening mechanism is the chameleon, where the scalar force is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Philip Chang , Lam Hui

The field equations of a generalized $f(R)$ type gravity model, in which there is an arbitrary coupling between matter and geometry, are obtained. The equations of motion for test particles are derived from a variational principle in the…

General Relativity and Quantum Cosmology · Physics 2009-05-26 T. Harko

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

We analyze seven different viable $f(R)$-gravities towards the Solar System tests and stochastic gravitational waves background. The aim is to achieve experimental bounds for the theory at local and cosmological scales in order to select…

High Energy Physics - Theory · Physics 2009-09-28 S. Capozziello , M. De Laurentis , S. Nojiri , S. D. Odintsov