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Related papers: Reconstructing cosmic expansion in $f(R, G)$ gravi…

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In this paper, we have investigated a bulk viscous anisotropic Universe and constrained its model parameters with recent $H(z)$ and Pantheon compilation data. Using cosmic chronometric technique, we estimate the present value of Hubble's…

General Relativity and Quantum Cosmology · Physics 2021-06-10 G. K. Goswami , Anil Kumar Yadav , B. Mishra , S. K. Tripathy

We prove here that Newtons universal gravitation and momentum conservation laws together reproduce Weinbergs relation. It is shown that the Hubble parameter H must be built in this relation, or equivalently the age of the Universe t. Using…

General Physics · Physics 2011-04-11 Antonio Alfonso-Faus

In this work, we obtain measurements of the Hubble constant in the context of modified gravity theories. We set up our theoretical framework by considering viable cosmological $f(R)$ and $f(T)$ models, and we analyzed them through the use…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-07 Rocco D'Agostino , Rafael C. Nunes

This study examines accelerated cosmic expansion using the Viscous Modified Chaplygin Gas (VMMG) and Generalized Cosmic Chaplygin Gas (GCCM) within Horava-Lifshitz gravity. Our aim is to constrain essential cosmological parameters, such as…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-12 Sayani Maity , Himanshu Chaudhary , Ujjal Debnath , S. K. Maurya , G. Mustafa

In this paper, we have investigated late time acceleration for a spatially flat dust filled Universe in Brans-Dicke theory in the presence of a positive cosmological constant $\Lambda$ . Expressions for Hubble's constant, luminosity…

General Relativity and Quantum Cosmology · Physics 2017-10-23 G. K. Goswami

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

The current tension between early- and late-Universe measurements of the Hubble constant ($H_0$), along with the still elusive nature of dark matter and dark energy, calls for model-independent probes of the Universe's expansion history.…

The fundamental nature and origin of dark energy are one of the premier mysteries of theoretical physics. In General Relativity Theory, the cosmological constant $\Lambda$ is the simplest explanation for dark energy. On the other hand, the…

General Relativity and Quantum Cosmology · Physics 2022-05-27 Raja Solanki , Avik De , Sanjay Mandal , P. K. Sahoo

Using comoving distance $d_c$ and angular diameter distance $d_A$, we recalculate parameters describing kinematical state of the universe, still combining the kinematical model of universe but not relying on dynamical equations for gravity.…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-27 Hai Huang , Long Huang

Nowadays, efforts are being devoted to the study of alternative cosmological scenarios in which modifications of General Relativity have been proposed to explain the late cosmic acceleration without assuming the existence of dark energy. In…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 Bruno Ribeiro , Armando Bernui , Marcela Campista

A new class of cosmological models in $f(R, T)$ modified theories of gravity proposed by Harko et al. (2011), where the gravitational Lagrangian is given by an arbitrary function of Ricci scalar $R$ and the trace of the stress-energy tensor…

General Physics · Physics 2014-07-15 Nasr Ahmed , Anirudh Pradhan

We address the issue of constraining the class of $f(\mathcal{R})$ able to reproduce the observed cosmological acceleration, by using the so called cosmography of the universe. We consider a model independent procedure to build up a…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Alejandro Aviles , Alessandro Bravetti , Salvatore Capozziello , Orlando Luongo

We study an isotropic flat FLRW-model in Scale-covariant theory of gravity $ f_{\gamma \delta}(\phi) $ \cite{Canuto:1977zz} which is explained in terms of ordinary and covariant differentiation of scalar field $ \phi $. As we know the…

General Relativity and Quantum Cosmology · Physics 2024-05-01 Shaily , J. K. Singh , Joao R. L. Santos , M. Zeyauddin

We investigate the prospects for determining the accelerating history of the Universe from upcoming measurements of the expansion rate $H(z)$. In our analyses, we use Monte Carlo simulations based on $w$CDM models to generate samples with…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-22 J. C. Carvalho , J. S. Alcaniz

In this paper, we consider a gravitational action containing a combination of the Ricci scalar, $R$, and the topological Gauss--Bonnet term, $G$. Specifically, we study the cosmological features of a particular class of modified gravity…

General Relativity and Quantum Cosmology · Physics 2023-03-15 Francesco Bajardi , Rocco D'Agostino

We propose a specialized parameterization for the Hubble parameter, inspired by $\Lambda$CDM cosmology, to investigate the cosmic expansion history of the Universe. This parameterization is employed to analyze the Universe's late-time…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-23 M. Koussour , N. Myrzakulov

In the present paper, we have investigated the Friedmann Robertson Walker (FRW) model in viable $f(R,T)$ gravity with $f(R,T)$ function proposed as $f(R,T)=R +\xi T^{1/2}$, where $\xi$ is an arbitrary constant, $R$ is the scalar curvature…

General Physics · Physics 2020-08-26 Nisha Godani , Gauranga C. Samanta

Compared with the plentiful researches of the Hubble parameter and deceleration factor, the third time derivative of the scale factor $a(t)$ in the FRW cosmology, namely, the jerk parameter $j$ still lacks attention. In order to study the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Zhong-Xu Zhai , Ming-Jian Zhang , Zhi-Song Zhang , Xian-Ming Liu , Tong-Jie Zhang

A new kind of evolution for cyclic models in which the Hubble parameter oscillates and keeps positive has been explored in a specific $f(R,T)$ gravity reconstruction. A singularity-free cyclic universe with negative varying cosmological…

General Relativity and Quantum Cosmology · Physics 2019-02-11 Nasr Ahmed , Sultan Z. Alamri

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