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Related papers: Constraining MOdified Gravity with the S2 Star

200 papers

Stage-IV surveys will enable unprecedented tests of gravity on cosmological scales. However, assuming General Relativity in the analysis of large-scale structure could introduce systematic biases if gravity deviates from GR at these scales.…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-27 Marc Alemany-Gotor , Cristian Viglione , Pablo Fosalba , Isaac Tutusaus

We investigate the application of an equation of state that incorporates corrections derived from the Snyder model (and the Generalized Uncertainty Principle) to describe the behavior of matter in a low-mass star. Remarkably, the resulting…

General Relativity and Quantum Cosmology · Physics 2023-12-05 Anna Pachoł , Aneta Wojnar

Most cosmological constraints on modified gravity are obtained assuming that the cosmic evolution was standard $\Lambda$CDM in the past and that the present matter density and power spectrum normalization are the same as in a $\Lambda$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Laura Taddei , Luca Amendola

We consider the cosmology where some function f(G) of the Gauss-Bonnet term G is added to the gravitational action to account for the late-time accelerating expansion of the universe. The covariant and gauge invariant perturbation equations…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Baojiu Li , John D. Barrow , David F. Mota

The accelerating expansion of our universe at present could be driven by an unknown energy component (Dark Energy) or a modification of general relativity (Modified Gravity). In this note we revisit the constraints on a phenomenological…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-03 Jun-Qing Xia

Using a perturbative approach we solve stellar structure equations for low-density (solar-type) stars whose interior is described with a polytropic equation of state in scenarios involving a subset of modified gravity theories. Rather than…

Solar and Stellar Astrophysics · Physics 2019-02-27 M. Cermeño , J. Carro , A. L. Maroto , M. Ángeles Pérez-García

The observed acceleration of the universe, explained through dark energy, could alternatively be explained through a modification of gravity that would also induce modifications in the evolution of cosmological perturbations. We use new…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-16 Ismael Tereno , Elisabetta Semboloni , Tim Schrabback

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

We consider a modified gravity theory, $f(R)=R+\alpha R^n-\frac{\mu^4}{R^m}$, in the metric formulation and analyze the contribution of electromagnetic field on the range of dynamical instability of a star filled with anisotropic matter.…

General Physics · Physics 2015-10-22 H. Rizwana Kausar , Ifra Noureen , M. Umair Shahzad

In this work, we introduce two models of the hybrid metric-Palatini theory of gravitation. We explore their background evolution, showing explicitly that one recovers standard General Relativity with an effective Cosmological Constant at…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-09 Nelson A. Lima , Vanessa Smer-Barreto

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

Within the effective field theory approach to cosmic acceleration, the background expansion can be specified separately from the gravitational modifications. We explore the impact of modified gravity in a background different from a…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Guilherme Brando , Felipe T. Falciano , Eric V. Linder , Hermano E. S. Velten

This paper simplifies the induced four-dimensional gravitational equations originating from a five-dimensional bulk within the framework of Nash's embeddings, incorporating them into a well-known $\mu-\Sigma$ modified gravity (MG)…

General Relativity and Quantum Cosmology · Physics 2024-06-12 Abraão J. S. Capistrano , Rafael C. Nunes , Luís A. Cabral

Since the discovery of the accelerated expansion of the Universe in 1998, modified gravity (MG) theories have attracted considerable attention as alternatives to dark energy (DE). While distinguishing the effects of MG from those of DE…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-16 Alejandro Aviles

We use galaxy-galaxy weak lensing data to perform a novel test on general relativity (GR) and $f(T)$ torsional gravity. In particular, we impose strong constraints using the torsional (teleparallel) formulation of gravity in which the…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-25 Zhaoting Chen , Wentao Luo , Yi-Fu Cai , Emmanuel N. Saridakis

A modified gravitational theory explains early universe and late time cosmology, galaxy and galaxy cluster dynamics. The modified gravity (MOG) theory extends general relativity (GR) by three extra degrees of freedom: a scalar field $G$,…

General Relativity and Quantum Cosmology · Physics 2020-10-30 J. W. Moffat

Deviations from general relativity, such as could be responsible for the cosmic acceleration, would influence the growth of large scale structure and the deflection of light by that structure. We clarify the relations between several…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Scott F. Daniel , Eric V. Linder , Tristan L. Smith , Robert R. Caldwell , Asantha Cooray , Alexie Leauthaud , Lucas Lombriser

We consider Horndeski modified gravity models obeying stability, velocity of gravitational waves $c_T$ equals $c$ and quasistatic approximation (QSA) on subhorizon scales. We assume further a $\Lambda$CDM background expansion and a…

General Relativity and Quantum Cosmology · Physics 2021-03-17 Radouane Gannouji , Leandros Perivolaropoulos , David Polarski , Foteini Skara

Model-independent parametrisations for examining departures from General Relativity have been increasingly studied over the past few years. Various observables have been used to constrain the parameters and forecasts for future surveys have…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-30 Daniel B. Thomas , Carlo R. Contaldi