English
Related papers

Related papers: Viable f(T) models are practically indistinguishab…

200 papers

Cosmography can be considered as a sort of a model-independent approach to tackle the dark energy/modified gravity problem. In this review, the success and the shortcomings of the $\Lambda$CDM model, based on General Relativity and standard…

General Relativity and Quantum Cosmology · Physics 2019-04-09 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

In this work, a new generic parameterisation for $f(R)$ theories is presented. Our proposal for a new equation of state can reproduce an $f(R)$-like evolution that describes late and early time universe within 1-$\sigma$ C.L when we use a…

General Relativity and Quantum Cosmology · Physics 2020-11-20 N. M. Jiménez Cruz , Celia Escamilla-Rivera

The expansion of the universe in $f(R,T)$ gravity is studied. By focusing on functions of the form $f(R,T)=f_1(R)+f_2(T)$, we assert that present day acceleration can be achieved if the functional form of $f_2(T)$ either grows slowly or…

General Relativity and Quantum Cosmology · Physics 2025-02-05 Vincent R. Siggia , Eric D. Carlson

We re-examine the growth index of the concordance $\Lambda$ cosmology in the light of the latest 6dF and {\em WiggleZ} data. In particular, we investigate five different models for the growth index $\gamma$, by comparing their cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Spyros Basilakos

In this work we perform an observational data analysis on the $f(R,T)$ gravity with the aim of constraining the parameter space of the model. Five different models are considered and the 30 point $z-H(z)$ cosmic chronometer data is used in…

General Relativity and Quantum Cosmology · Physics 2021-05-24 Prabir Rudra , Kinsuk Giri

We study the growth of matter density perturbations delta_m for a number of viable f(R) gravity models that satisfy both cosmological and local gravity constraints, where the Lagrangian density f is a function of the Ricci scalar R. If the…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Shinji Tsujikawa , Radouane Gannouji , Bruno Moraes , David Polarski

To better distinguish the nature of $H_0$ and $S_8$ tensions, it is necessary to separate the effects of expansion and the growth of structure. The growth index $\gamma$ was identified as the most important parameter that characterizes the…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-01 Cemsinan Deliduman , Furkan Şakir Dilsiz , Selinay Sude Binici

Modified gravity has attracted much attention over the last few years and remains a potential candidate for dark energy. In particular, the so-called viable f(R) gravity theories, which are able to both recover General Relativity (GR) and…

General Relativity and Quantum Cosmology · Physics 2016-04-20 Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby , Sulona Kandhai , Diego Saez-Gomez

We investigate the evolution of scalar perturbations in $f(T)$ teleparallel gravity and its effects on the cosmic microwave background (CMB) anisotropy. The $f(T)$ gravity generalizes the teleparallel gravity which is formulated on the…

General Relativity and Quantum Cosmology · Physics 2018-05-22 Rafael C. Nunes

Teleparallel gravity offers a competing geometric framework on which to build cosmological models. The Gauss-Bonnet invariant captures key aspects of the underlying geometry that has been shown to be an interesting way to form cosmological…

General Relativity and Quantum Cosmology · Physics 2026-03-03 Shivam Kumar Mishra , Jackson Levi Said , B. Mishra

We study the background cosmology of the ghost-free, bimetric theory of gravity. We perform an extensive statistical analysis of the model using both frequentist and Bayesian frameworks and employ the constraints on the expansion history of…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-22 Yashar Akrami , Tomi S. Koivisto , Marit Sandstad

Forecast constraints for a Symmetric Teleparallel Gravity model with a $\Lambda$CDM background are made using forthcoming ground and space based gravitational waves observatories. A Bayesian analysis resorting to generated mock catalogs…

Cosmology and Nongalactic Astrophysics · Physics 2022-10-20 José Ferreira , Tiago Barreiro , José Mimoso , Nelson J. Nunes

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

Two different realistic $F(R)$ modified gravity models are considered in the framework of the Friedmann-Lemetre-Robertson-Walker universe. The parameters of these two models are adjusted to reach coherence with the most recent and accurate…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Antonio Jesús López-Revelles

We investigate the observational implications of a gravitational model wherein the gravitational constant $G$ and the cosmological constant $\Lambda$ exhibit scale-dependent behavior at the perturbative level, while preserving the General…

General Relativity and Quantum Cosmology · Physics 2025-05-06 Wiliam S. Hipólito-Ricaldi , Rodrigo von Marttens , Felipe de Melo-Santos , Davi C. Rodrigues

Considering a well-motivated $f(R)$ modified-gravity model, in which an exponential function of the curvature is included, in this paper we implement a statistical data analysis to set constraints on the parameters of the model, taking into…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-01 Mario A. Acero , A. Oliveros

This study offers a comprehensive reconstruction of $f(T)$ gravity model with three distinct non-linear as well as novel forms employing a hybrid scale factor to depict the expansion history of the universe starting from early decelerated…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Suraj Kumar Behera , Pratik P. Ray

Recent re-calibration of the Type Ia supernova (SNe~Ia) magnitude-redshift relation combined with cosmic microwave background (CMB) and baryon acoustic oscillation (BAO) data have provided excellent constraints on the standard cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 Suhail Dhawan , Ariel Goobar , Edvard Mörtsell , Rahman Amanullah , Ulrich Feindt

One of the so-called viable modified gravities is analyzed. This kind of gravity theories are characterized by a well behavior at local scales, where General Relativity is recovered, while the modified terms become important at the…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Diego Sáez-Gómez

We investigate f(T) cosmology in both the background, as well as in the perturbation level, and we present the general formalism for reconstructing the equivalent one-parameter family of f(T) models for any given dynamical dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-18 James B. Dent , Sourish Dutta , Emmanuel N. Saridakis
‹ Prev 1 4 5 6 7 8 10 Next ›