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We perform a cosmological test of Cotton gravity, which describes gravity by cotton tensor. We assume in Cotton gravity the background evolution is the same as the flat FLRW background. We derive the cosmological perturbation theory of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-23 Pengbo Xia , Dongdong Zhang , Xin Ren , Bo Wang , Yen Chin Ong

In a modified gravity theory, the propagation equation of gravitational waves will be presented in a non-standard way. Therefore this tenor mode perturbation of time-space, as a complement to the scalar mode perturbation, provides a unique…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Lixin Xu

We study the cosmic microwave background (CMB) in the framework of the degenerate higher-order scalar-tensor (DHOST) theory to test gravity theories. This theoretical framework includes the wide class of dark energy models such as the…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-28 Takashi Hiramatsu , Daisuke Yamauchi

We consider spatially covariant modified gravity in which the would-be scalar degree of freedom is made non-dynamical and hence there are just two tensorial degrees of freedom, i.e., the same number of dynamical degrees of freedom as in…

General Relativity and Quantum Cosmology · Physics 2021-12-15 Aya Iyonaga , Tsutomu Kobayashi

The recent measurements of Cosmic Microwave Background temperature and polarization anisotropies made by the Planck satellite have provided impressive confirmation of the $\Lambda$CDM cosmological model. However interesting hints of slight…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

We report strong cosmological constraints on the Brans-Dicke (BD) theory of gravity using Cosmic Microwave Background data from Planck.We consider two types of models. First, the initial condition of the scalar field is fixed to give the…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-09 A. Avilez , C. Skordis

We investigate the impact on cosmological observables of $f(Q)$-gravity, a specific class of modified gravity models in which gravity is described by the non-metricity scalar, $Q$. In particular we focus on a specific model which is…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-24 Noemi Frusciante

We show that modified gravity presents distinctive nonlinear features on the Cosmic Microwave Background (CMB) anisotropies comparing with General Relativity (GR). We calculate the contribution to the CMB non-Gaussianity from nonlinear…

General Relativity and Quantum Cosmology · Physics 2011-08-09 Xian Gao

Cosmological constraints on the scalar-tensor theory of gravity by analyzing the angular power spectrum data of the cosmic microwave background (CMB) obtained from the Planck 2015 results are presented. We consider the harmonic attractor…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Junpei Ooba , Kiyotomo Ichiki , Takeshi Chiba , Naoshi Sugiyama

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 is a pedagogical introduction to models of gravity and how to constrain them through cosmological observations. We focus on the Horndeski scalar-tensor theory and on the quantities that can be measured with a minimum of…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-27 Luca Amendola , Dario Bettoni , Ana Marta Pinho , Santiago Casas

We investigate the cosmological observational test of the extended quintessence model, i.e. a scalar-tensor gravity model with a scalar field potential serving as dark energy, by using the Planck 2018 cosmic microwave background (CMB) data,…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 Gong Cheng , Fengquan Wu , Xuelei Chen

We use measurements from the Planck satellite mission and galaxy redshift surveys over the last decade to test three of the basic assumptions of the standard model of cosmology, $\Lambda$CDM: the spatial curvature of the universe, the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Shadab Alam , Shirley Ho , Alessandra Silvestri

The cosmological phenomenology of gravity is typically studied in two limits: relativistic perturbation theory (on large scales) and Newtonian gravity (required for smaller, non-linear, scales). Traditional approaches to model-independent…

General Relativity and Quantum Cosmology · Physics 2020-07-21 Daniel B Thomas

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

In this letter, we investigate cosmology within the framework of modified $f(Q, L_m)$ gravity using the non-linear model $f(Q, L_m) = -Q + \alpha L_m^n + \beta$, where $\alpha$, $\beta$, and $n$ are free parameters. The modified Friedmann…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-02 Y. Myrzakulov , Alnadhief H. A. Alfedeel , M. Koussour , S. Muminov , E. I. Hassan , J. Rayimbaev

Most of the information on our cosmos stems from either late-time observations or the imprint of early-time inhomogeneities on the cosmic microwave background. We explore to what extent early modifications of gravity, which become…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-10 Nelson A. Lima , Vanessa Smer-Barreto , Lucas Lombriser

We investigate the metric perturbations of the restricted f(R) theory of gravity in the cosmological context and explore the phenomenological implications of this model. We show that it is possible to construct a restricted model of…

General Relativity and Quantum Cosmology · Physics 2017-04-12 M. Chaichian , A. Ghalee , J. Kluson

We investigate the cosmological and the local tests of the f(R) theory of modified gravity via the observations of (1) the cosmic expansion and (2) the cosmic structures and via (3) the solar-system experiments. To fit the possible cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Wei-Ting Lin , Je-An Gu , Pisin Chen

In this paper we introduce a new public Einstein-Boltzmann solver, \texttt{MGCLASS II}, built as a modification to the publicly available \texttt{CLASS} code, that allows to obtain cosmological observables for Modified Gravity theories. It…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-28 Ziad Sakr , Matteo Martinelli
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