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Related papers: Cosmography in f(T)-gravity

200 papers

We propose a method to probe the homogeneity of a general universe, without assuming symmetry. We show that isotropy can be tested at remote locations on the past lightcone by comparing the line-of-sight and transverse expansion rates,…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-05 Raul Jimenez , Roy Maartens , Ali Rida Khalifeh , Robert R. Caldwell , Alan F. Heavens , Licia Verde

We derive the most general homogeneous and isotropic teleparallel geometries, defined by a metric and a flat, affine connection. We find that there are five branches of connection solutions, which are connected via several limits, and can…

General Relativity and Quantum Cosmology · Physics 2023-04-25 Lavinia Heisenberg , Manuel Hohmann , Simon Kuhn

It is known that de Rham-Gabadadze-Tolley (dRGT) massive gravity does not permit a homogeneous and isotropic universe with flat or spherical spatial metrics. We demonstrate that a singular reference metric solves this problem in an economic…

General Relativity and Quantum Cosmology · Physics 2019-01-29 Hongsheng Zhang , Ya-Peng Hu , Yi Zhang

In this paper, we present the cosmological scenario obtained from $f(R,T)$ gravity by using an exponential dependence on the trace of the energy-momentum tensor. With a numerical approach applied to the equations of motion, we show several…

General Relativity and Quantum Cosmology · Physics 2019-11-11 G. Ribeiro , R. Sfair , P. H. R. S. Moraes , J. R. L. Santos , A. de Souza Dutra

We consider the cosmology of a brane-world scenario in the framework of teleparallel and $f(T)$ gravity in a way that matter is localized on the brane. We show that the cosmology of such branes is different from the standard cosmology in…

General Relativity and Quantum Cosmology · Physics 2015-04-02 K. Atazadeh , A. Eghbali

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 use cosmography to present constraints on the kinematics of the Universe, without postulating any underlying theoretical model. To this end, we use a Monte Carlo Markov Chain analysis to perform comparisons to the supernova Ia Union 2…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Alejandro Aviles , Christine Gruber , Orlando Luongo , Hernando Quevedo

Cosmology faces a pressing challenge with the Hubble constant ($H_0$) tension, where the locally measured rate of the Universe's expansion does not align with predictions from the cosmic microwave background (CMB) calibrated with…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-27 Rebecca Briffa , Celia Escamilla-Rivera , Jackson Levi Said , Jurgen Mifsud

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

The problem of reproducing dark energy effects is reviewed here with particular interest devoted to cosmography. We summarize some of the most relevant cosmological models, based on the assumption that the corresponding barotropic equations…

General Relativity and Quantum Cosmology · Physics 2013-12-09 Salvatore Capozziello , Mariafelicia De Laurentis , Orlando Luongo , Alan Cosimo Ruggeri

The cosmological principle is fundamental to the standard cosmological model. It assumes that the Universe is homogeneous and isotropic on very large scales. As the basic assumption, it must stand the test of various observations. In this…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-13 J. P. Hu , Y. Y. Wang , J. Hu , F. Y. Wang

We consider the cosmologies that arise in a subclass of f(R) gravity with f(R)=R+\mu ^{2n+2}/(-R)^{n} and -1<n<0 in the metric (as opposed to the Palatini) variational approach to deriving the gravitational field equations. The calculations…

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

We use dynamical system methods to explore the general behaviour of $f(T)$ cosmology. In contrast to the standard applications of dynamical analysis, we present a way to transform the equations into a one-dimensional autonomous system,…

General Relativity and Quantum Cosmology · Physics 2018-03-14 A. Awad , W. El Hanafy , G. G. L. Nashed , Emmanuel N. Saridakis

Refined astrometry measurements allow us to detect large-scale deviations from isotropy through real-time observations of changes in the angular separation between sources at cosmic distances. This "cosmic parallax" effect is a powerful…

Astrophysics · Physics 2009-06-16 Claudia Quercellini , Miguel Quartin , Luca Amendola

Much of modern cosmology relies on the Cosmological Principle, the assumption that the Universe is isotropic and homogeneous on sufficiently large scales, but it remains worthwhile to examine cosmological models that violate this principle…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-01 Ananda F. Smith , Craig J. Copi , Glenn D. Starkman

We establish new constraints on $f(T)$ gravity models by using cosmological data. In particular, we investigate the restrictions given by the gas mass fraction measurements of galaxy clusters and transversal BAO data. Both data sets are…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-28 F. B. M. dos Santos , J. E. Gonzalez , R. Silva

Cosmography is the tool that makes possible to untie the interpretation of cosmological observations from the definition of any dynamical prior. We review the constraints on the cosmographic parameter obtained using the most thorough data…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-01 Vincenzo Vitagliano , Jun-Qing Xia , Stefano Liberati , Matteo Viel

Teleparallel gravity is a modified theory of gravity for which the Ricci scalar $R$ of the underlying geometry in the action is replaced by an arbitrary functional form of torsion scalar $T$. In doing so, cosmology in $% f(T)$ gravity…

General Physics · Physics 2022-07-20 Sanjay Mandal , Snehasish Bhattacharjee , S. K. J. Pacif , P. K. Sahoo

We have investigated the evolution of a homogeneous isotropic background of the Universe and inhomogeneous subhorizon matter density perturbations in viable $f(R)$ models of present dark energy and cosmic acceleration analytically and…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-05 Hayato Motohashi , Alexei A. Starobinsky , Jun'ichi Yokoyama

We have investigated an isotropic and homogeneous cosmological model of the universe in $f(R, T^{\phi})$ gravity, where $T^{\phi}$ is the trace of the energy-momentum tensor and $R$ is the Ricci scalar. We developed and presented exact…

General Relativity and Quantum Cosmology · Physics 2023-08-10 Vinod Kumar Bhardwaj , Priyanka Garg