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Related papers: Growth factor in f(T) gravity

200 papers

Prompted by the recent more precise determination of the basic cosmological parameters and growing evidence that the matter-energy content of the universe is now dominated by dark energy and dark matter we present the general solution of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Marek Demianski , Zdzislaw A. Golda , Andrzej Woszczyna

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

We use large volume N-body simulations to predict the clustering of dark matter in redshift space in f(R) modified gravity cosmologies. This is the first time that the nonlinear matter and velocity fields have been resolved to such a high…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 Elise Jennings , Carlton M. Baugh , Baojiu Li , Gong-Bo Zhao , Kazuya Koyama

We use observations related to the variation of fundamental constants, in order to impose constraints on the viable and most used $f(T)$ gravity models. In particular, for the fine-structure constant we use direct measurements obtained by…

General Relativity and Quantum Cosmology · Physics 2017-04-18 Rafael C. Nunes , Alexander Bonilla , Supriya Pan , Emmanuel N. Saridakis

We investigate the damping of gravitational waves (GW) in $f(R)$ gravity by matter. By applying the kinetic theory, we examine the first-order approximation of the relativistic Boltzmann equation. In the flat spacetime, we derive the…

General Relativity and Quantum Cosmology · Physics 2025-03-13 Haiyuan Feng , Laiyuan Su , Rong-Jia Yang , Wei-Qiang Chen

Alterations of the gravity Lagrangian introduced in modified torsion gravity theories---also referred to as $f(T)$ gravity---allows for an accelerated expansion in a matter dominated Universe. In this framework, the cosmic speed up is…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-23 Stefano Camera , Vincenzo F. Cardone , Ninfa Radicella

We study the degeneracies between neutrino mass and dark energy as they manifest themselves in cosmological observations. In contradiction to a popular formula in the literature, the suppression of the matter power spectrum caused by…

Astrophysics · Physics 2008-11-26 Angeliki Kiakotou , Oystein Elgaroy , Ofer Lahav

We investigate the formation of the large scale structures in the present accelerated era in $f(R)$ gravity background. This is done by considering the linear growth of matter perturbations at low redshift $z<1$. The effect of $f(R)$ alters…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-15 Ajay Kumar Sharma , Murli Manohar Verma

In this paper, we study the $f(T,\mathcal{T})$ gravity model in the presence of the bulk viscosity by the flat-FRW metric. The field equation is obtained by teleparallel gravity with tetrad field. The universe components are considered as…

General Relativity and Quantum Cosmology · Physics 2020-12-18 T. Mirzaei-Rezaei , Alireza Amani , E. Yusofi , S. Rouhani , M. A. Ramzanpour

We investigate the growth index parameter \gamma and the time variation of the gravitational constant G_{eff} by using the currently available growth function f(z) data at different redshifts, with and without scaling to the fiducial…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-05 Seokcheon Lee

A single parameter, the gravitational growth index \gamma, succeeds in characterizing the growth of density perturbations in the linear regime separately from the effects of the cosmic expansion. The parameter is restricted to a very narrow…

Astrophysics · Physics 2010-11-05 Eric V. Linder , Robert N. Cahn

Recently, a novel Einstein-Gauss-Bonnet gravity in four dimensions has been introduced [Phys. Rev. Lett. 124 (2020) 081301]. We will investigate cosmological consequences of this model in details. We will consider linear matter density…

General Relativity and Quantum Cosmology · Physics 2020-10-05 Zahra Haghani

The growth rate of matter perturbations can be used to distinguish between different gravity theories and to distinguish between dark energy and modified gravity at cosmological scales as an explanation to the observed cosmic acceleration.…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-22 Mustapha Ishak , Jason Dossett

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

An accelerated expansion phase is being experienced by the universe due to the presence of an unknown energy component known as dark energy (DE). To find out the cosmic evolution scientists ever tried to modify Einstein's gravitational…

General Physics · Physics 2018-11-14 M. Zubair , M. Zeeshan

In this paper, the dynamical behavior of the accelerated expansion of the universe is studied within the framework of $f(T)$ gravity by considering a well-motivated functional form of $f(T)$. A specific form of the Hubble parameter is…

General Relativity and Quantum Cosmology · Physics 2026-03-20 Khomesh R. Patle , G. P. Singh

In the context of f(R, T) gravity theory for the flat Friedmann Lemaitre Robertson Walker (FLRW) model, the accelerating expansion of the universe is investigated using a specific form of the emergent Hubble parameter. Datasets from H(z),…

General Relativity and Quantum Cosmology · Physics 2025-01-16 N. Myrzakulov , S. H. Shekh , Anirudh Pradhan , Archana Dixit

The theoretical and observational consequences of thermodynamics of open systems, which allow particle creation are investigated in modified $f(R,T)$ ($R$ is the Ricci scalar and $T$ is the trace of energy-momentum tensor) theory of gravity…

General Relativity and Quantum Cosmology · Physics 2014-08-26 C. P. Singh , Vijay Singh

Using techniques from singular perturbation theory, we explicitly calculate the cosmological evolution in a class of modified gravity models. By considering the (m)CDTT model, which aims to explain the current acceleration of the universe…

Astrophysics · Physics 2009-06-23 Jonathan D. Evans , Lisa M. H. Hall , Philippe Caillol

The growth index $\gamma$ is an interesting tool to assess the phenomenology of dark energy (DE) models, in particular of those beyond general relativity (GR). We investigate the possibility for DE models to allow for a constant $\gamma$…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-31 David Polarski , Alexei A. Starobinsky , Hector Giacomini