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Related papers: Constraining MOdified Gravity with the S2 Star

200 papers

The measurement of the size of gravitationally bounded structures is an important test of gravity theories. For a given radius different theories can in fact predict a different gravitational stability mass (GSM) necessary to ensure the…

General Relativity and Quantum Cosmology · Physics 2020-06-18 Camilo Santa , Antonio Enea Romano

Of many extended theories of gravity, $f(R,T)$ gravity has gained reasonable interest in recent times as it provides interesting results in cosmology. Logarithmic corrections in modified theories of gravity has been studied extensively. In…

General Relativity and Quantum Cosmology · Physics 2024-09-05 Biswajit Deb , Atri Deshamukhya

We present forecasted cosmological constraints from combined measurements of galaxy cluster abundances from the Simons Observatory and galaxy clustering from a DESI-like experiment on two well-studied modified gravity models, the…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-05 Rayne Liu , Georgios Valogiannis , Nicholas Battaglia , Rachel Bean

We propose a modified gravity theory that propagates only two local gravitational degrees of freedom and that does not have an Einstein frame. According to the classification in JCAP 01 (2019) 017 [arXiv:1810.01047 [gr-qc]], this is a…

General Relativity and Quantum Cosmology · Physics 2020-09-17 Antonio De Felice , Andreas Doll , Shinji Mukohyama

Solar System tests give nowadays constraints on the estimated value of the cosmological constant, which can be accurately derived from different experiments regarding gravitational redshift, light deflection, gravitational time-delay and…

Astrophysics · Physics 2008-11-26 Gianluca Allemandi , Matteo Luca Ruggiero

The subject of this paper is to investigate the weak regime covariant scalar-tensor-vector gravity (STVG) theory, known as the MOdified gravity (MOG) theory of gravity. First, we show that the MOG in the absence of scalar fields is…

General Relativity and Quantum Cosmology · Physics 2018-10-09 M. Khurshudyan , N. S. Mazhari , D. Momeni , R. Myrzakulov , M. Raza

We consider theories with an arbitrary coupling between matter and gravity and obtain the perturbation equation of matter on subhorizon scales. Also, we derive the effective gravitational constant $G_{eff}$ and two parameters $\Sigma$ and…

Astrophysics · Physics 2009-12-17 Savvas Nesseris

We present forecasts for constraints on the Hu \& Sawicki $f(R)$ modified gravity model using realistic mock data representative of future cluster and weak lensing surveys. We create mock thermal Sunyaev-Zel'dovich effect selected cluster…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-11 Sophie M. L. Vogt , Sebastian Bocquet , Christopher T. Davies , Joseph J. Mohr , Fabian Schmidt

We use the Allen et al. (2008) galaxy cluster gas mass fraction versus redshift data to constrain parameters of three different dark energy models: a cosmological constant dominated one ($\Lambda$CDM); the XCDM parameterization of dark…

Astrophysics · Physics 2010-11-11 Lado Samushia , Bharat Ratra

This paper analyses the cosmological consequences of a modified theory of gravity whose action integral is built from a linear combination of the Ricci scalar $R$ and a quadratic term in the covariant derivative of $R$. The resulting…

General Relativity and Quantum Cosmology · Physics 2015-12-31 R. R. Cuzinatto , C. A. M. de Melo , L. G. Medeiros , P. J. Pompeia

One way to account for the acceleration of the universe is to modify general relativity, rather than introducing dark energy. Typically, such modifications introduce new degrees of freedom. It is interesting to consider models with no new…

Astrophysics · Physics 2011-05-12 Sean M. Carroll , Ignacy Sawicki , Alessandra Silvestri , Mark Trodden

There is a distinct possibility that current and future cosmological data can be used to constrain Einstein's theory of gravity on the very largest scales. To be able to do this in a model-independent way, it makes sense to work with a…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-13 Tessa Baker , Pedro G. Ferreira , Constantinos Skordis , Joe Zuntz

In this paper we investigate a Yukawa gravity modification of the Newtonian gravitational potential in a weak field approximation. For that purpose we derived the corresponding equations of motion and used them to perform two-body…

Astrophysics of Galaxies · Physics 2023-05-05 P. Jovanović , V. Borka Jovanović , D. Borka , A. F. Zakharov

We report an updated constraint on the Solar System quadrupole parameter $Q_2$, which encodes the external field effect predicted by modified gravity versions of the MOND paradigm. Using the dataset employed to compute the DE440 planetary…

General Relativity and Quantum Cosmology · Physics 2026-02-24 R. S. Park , A. Hees , B. Famaey , H. Desmond , A. Durakovic

We provide the modified TOV equations for the hydrostatic equilibrium of charged compact stars within the metric $f(R)$ gravitational background. We adopt the MIT bag model EoS for the dense matter and assume a charge distribution where the…

General Relativity and Quantum Cosmology · Physics 2022-09-23 Juan M. Z. Pretel , José D. V. Arbañil , Sergio B. Duarte , Sergio E. Jorás , Ribamar R. R. Reis

In the framework of $f(T)$ gravity, we focus on a weak-field and spherically symmetric solution for the Lagrangian $f(T)=T+\alpha T^{2}$, where $\alpha$ is a small constant which parameterizes the departure from General Relativity. In…

General Relativity and Quantum Cosmology · Physics 2016-05-16 Matteo Luca Ruggiero

Viable modifications of gravity on cosmological scales predominantly rely on screening mechanisms to recover Einstein's Theory of General Relativity in the Solar System, where it has been well tested. A parametrisation of the effects of…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-23 Lucas Lombriser

The thermodynamics-gravity conjecture reveals that one can derive the gravitational field equations by using the first law of thermodynamics and vice versa. Considering the entropy associated with the horizon in the form of non-extensive…

General Relativity and Quantum Cosmology · Physics 2021-11-04 Mahnaz Asghari , Ahmad Sheykhi

We show that fundamental plane of elliptical galaxies can be used to obtain observational constraints on metric theories of gravity. Being it connected to global properties of ellipticals, it can fix parameters of modified gravity.…

General Relativity and Quantum Cosmology · Physics 2020-04-27 Salvatore Capozziello , Vesna Borka Jovanović , Duško Borka , Predrag Jovanović