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Related papers: Cosmographic transition redshift in $f(R)$ gravity

200 papers

We have explored a transitioning cosmic model, depicting late-time accelerated expansion in $f(R,T^{\phi})$ theory of gravity for an isotropic and homogeneous universe, where the trace of energy-momentum tensor $T^{\phi}$ is the function of…

General Relativity and Quantum Cosmology · Physics 2024-03-29 Bhojraj Singh Jayas , Vinod Kumar Bhardwaj

We compile a list of 28 independent measurements of the Hubble parameter between redshifts 0.07 < z < 2.3 and use this to place constraints on model parameters of constant and time-evolving dark energy cosmologies. These H(z) measurements…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Omer Farooq , Bharat Ratra

In modern cosmology, the curiosity of ultimately understanding the nature of the dark energy controlling the recent acceleration of the Universe motivates us to explore its properties by using some novel approaches. In this work, to explore…

General Relativity and Quantum Cosmology · Physics 2023-12-19 Sanjay Mandal , Sneha Pradhan , P. K. Sahoo , Tiberiu Harko

In this paper, a specific family of $f(R)$ models that can produce the $\Lambda$CDM background expansion history is constrained by using the currently available geometric and dynamic probes. The scale dependence of the growth rate $f(z,k)$…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Lixin Xu

In this paper, we consider a comprehensive investigation of the cosmological model described by $f(R,T) = R + 2\lambda T$ (where $\lambda$ represents a free parameter) in light of the most recent observational data. By constraining the…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-29 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , E. I. Hassan

Several key relations are derived for Cosmological General Relativity which are used in standard observational cosmology. These include the luminosity distance, angular size, surface brightness and matter density. These relations are used…

Astrophysics · Physics 2008-11-26 John G. Hartnett , Firmin J. Oliveira

In this work, we present a method for numerically solving the Friedmann equations of modified $f(\mathcal{G})$ gravity in the presence of pressureless matter. This method enables us to predict the redshift behaviour of the Hubble expansion…

General Relativity and Quantum Cosmology · Physics 2024-11-08 Santosh V. Lohakare , Soumyadip Niyogi , B. Mishra

In the last few decades, extensions of General Relativity have reached always more attention especially in view of possible breakdowns of the standard $\Lambda$CDM paradigm at intermediate and high redshift regimes. If General Relativity…

General Relativity and Quantum Cosmology · Physics 2020-03-19 Marco Calzà , Alessandro Casalino , Orlando Luongo , Lorenzo Sebastiani

The explanation of the accelerated expansion of the Universe poses one of the most fundamental questions in physics and cosmology today. If the acceleration is driven by some form of dark energy, one can try to constrain the parameters…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Marek Demianski , Ester Piedipalumbo , Claudio Rubano , Paolo Scudellaro

We concentrate on the cosmological properties in the Tsujikawa model (TM) of viable $f(R)$ gravity with the dynamical background evolution and linear perturbation theory by using the CosmoMC package. We study the constraints of the…

General Relativity and Quantum Cosmology · Physics 2019-09-02 Jian-Yong Cen , Shang-Yu Chien , Chao-Qiang Geng , Chung-Chi Lee

We investigate the viable exponential $f(R)$ gravity in the metric formalism with $f(R)=-\beta R_s (1-e^{-R/R_s})$. The latest sample of the Hubble parameter measurements with 23 data points is used to place bounds on this $f(R)$ model. A…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Yun Chen , Chao-Qiang Geng , Chung-Chi Lee , Ling-Wei Luo , Zong-Hong Zhu

The oscillating scenario of route to Lambda was recently proposed by us arXiv:0704.1651 as an alternative to a cosmological constant in a explanation of the current accelerating universe. In this scenario phantom scalar field conformally…

Astrophysics · Physics 2008-11-26 Aleksandra Kurek , Orest Hrycyna , Marek Szydlowski

The standard relation between the cosmological redshift and cosmic scale factor underlies cosmological inference from virtually all kinds of cosmological observations, leading to the emergence of the LambdaCDM cosmological model. This…

Cosmology and Nongalactic Astrophysics · Physics 2019-08-08 Radosław Wojtak , Francisco Prada

We investigate late-time cosmology in the context of modified $f(Q,L_m)$ gravity, considering a non-linear model$ f(Q,L_m) = \alpha Q + \beta L_m^n + \lambda$ where, $\alpha$, $\beta$, $\lambda$, and $n$ are some free parameters. The…

General Relativity and Quantum Cosmology · Physics 2026-01-16 Rajdeep Mazumdar , Kalyan Malakar , Kalyan Bhuyan

The observed accelerated expansion of the Universe may be explained by dark energy or the breakdown of general relativity (GR) on cosmological scales. When the latter case, a modified gravity scenario, is considered, it is often assumed…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-04 Jiro Matsumoto , Teppei Okumura , Misao Sasaki

The theoretical framework of cosmology is mainly defined by gravity, of which general relativity is the current model. Recent tests of general relativity within the \Lambda Cold Dark Matter (CDM) model have found a concordance between…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-30 Radoslaw Wojtak , Steen H. Hansen , Jens Hjorth

In light of the statistical performance of cosmological observations, in this work we present the cosmography in $f(T,B)$ gravity. In this scenario we found a cosmological viable standard case that allows to reduce the degeneracy between…

General Relativity and Quantum Cosmology · Physics 2021-11-17 Celia Escamilla-Rivera , Geovanny A. Rave-Franco , Jackson Levi Said

Using linear perturbation theory and the Friedmann-Lemaitre solutions of the cosmological field equations, we derive analytically a second-order differential equation for the evolution of the linear bias factor, b(z), between the background…

Astrophysics · Physics 2009-10-31 Spyros Basilakos , Manolis Plionis

In this work, we investigate a cosmological model within modified teleparallel gravity using two functional forms of $f(T)$: a hybrid model $f(T)=e^{\gamma T}T^{\sigma}$ and a logarithmic model, in the context of a periodic cosmic evolution…

General Relativity and Quantum Cosmology · Physics 2026-05-13 F. Mavoa , M. C . Sow , H. Hova C. S. Touré , M. G. Ganiou

Understanding the expansion of the Universe remains a profound challenge in fundamental physics. The complexity of solving General Relativity equations in the presence of intricate, inhomogeneous flows has compelled cosmological models to…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-18 P. Tremblin , G. Chabrier