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A new parametrization of the Hubble parameter is proposed to explore the issue of the cosmological landscape. The constraints on model parameters are derived through the Markov Chain Monte Carlo (MCMC) method by employing a comprehensive…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-06 L. Sudharani , Kazuharu Bamba , N. S. Kavya , V. Venkatesha

The present work is based on a parametric reconstruction of the deceleration parameter $q(z)$ in a model for the spatially flat FRW universe filled with dark energy and non-relativistic matter. In cosmology, the parametric reconstruction…

General Relativity and Quantum Cosmology · Physics 2017-09-13 Abdulla Al Mamon , Sudipta Das

In this paper, three kinds of simple parameterized deceleration parameters $q(z)=a+\frac{b z}{1+z}$, $q(z)=a+\frac{b z}{(1+z)^2}$ and $q(z)={1/2}+\frac{a z+b}{(1+z)^2}$ are reconstructed from the latest Sne Ia Gold dataset, observational…

Astrophysics · Physics 2009-11-13 Lixin Xu , Chengwu Zhang , Baorong Chang , Hongya Liu

In this article, we introduce an innovative parametric representation of the Hubble parameter, providing a model-independent means to explore the dynamics of an accelerating cosmos. The model's parameters are rigorously constrained through…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-16 M. Koussour , N. Myrzakulov , M. K. M. Ali

This article discusses a dark energy cosmological model in the standard theory of gravity - general relativity with a broad scalar field as a source. Exact solutions of Einstein's field equations are derived by considering a particular form…

General Relativity and Quantum Cosmology · Physics 2022-08-23 S. K. J. Pacif , Simran Arora , P. K. Sahoo

We present a new $f(Q)$ cosmological model capable of reproducing late-time acceleration, i.e. $f\left( Q\right) = \lambda_{0}\left( \lambda +Q\right) ^{n}$ by supporting certain parametrization of the Hubble parameter. By using…

General Relativity and Quantum Cosmology · Physics 2023-06-26 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

We compile a complete collection of reliable Hubble parameter $H(z)$ data to redshift $z \leq 2.36$ and use them with the Gaussian Process method to determine continuous $H(z)$ functions for various data subsets. From these continuous…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-04 Hai Yu , Bharat Ratra , Fa-Yin Wang

We study a parametrization of the deceleration parameter in a tilted universe, namely a cosmological model equipped with two families of observers. The first family follows the smooth Hubble flow, while the second are the real observers…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Kerkyra Asvesta , Lavrentios Kazantzidis , Leandros Perivolaropoulos , Christos G. Tsagas

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

We perform a comprehensive observational test of a canonical quintessence model driven by an exponential potential, motivated by its emergence in higher-dimensional theories, string-inspired scenarios, and modified gravity. Using a Markov…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Sanjeeda Sultana , Surajit Chattopadhyay

We investigated a time-varying cosmological constant model using recent BAO measurements from DESI DR2, combined with Type Ia supernova samples (Pantheon$^{+}$, DES-Dovekie, and Union3) and CMB shift parameters, to constrain the…

General Relativity and Quantum Cosmology · Physics 2026-02-17 Himanshu Chaudhary , Ratul Mandal , Masroor Bashir , Vipin Kumar Sharma , Ujjal Debnath

This paper introduces a novel cosmological model aimed at probing the accelerated expansion of the late Universe through a unique parametrization of the deceleration parameter. We aim to constrain key cosmic parameters by integrating recent…

General Relativity and Quantum Cosmology · Physics 2024-08-14 Himanshu Chaudhary , Ujjal Debnath , G. Mustafa , S. K. Maurya , Farruh Atamurotov

In this work, we have considered a model independent approach to study the nature of the late time cosmic acceleration. We have used the Pade approximation to parametrize the comoving distance. Consequently, from this comoving distance, we…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-09 Bikash R. Dinda

We further investigate slowing down of acceleration of the universe scenario for five parametrizations of the equation of state of dark energy using four sets of supernovae data. In a maximal probability analysis we also use the baryon…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-08 Juan Magaña , Víctor H. Cárdenas , V. Motta

By incorporating the curvature $\Omega_k$ as a free parameter, it has been found that the tension between the high redshift CMB shift parameter $R(z^{\ast})$ data and the low redshift SNIa and BAO data from the combination of SDSS and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Jianmang Lin , Puxun Wu , Hongwei Yu

We study the constraints on dark energy equation of state $\omega^{X}$ and the deceleration parameter $q$ from the recent observational data including Hubble data and the cosmic microwave background (CMB) radiation by using a…

General Relativity and Quantum Cosmology · Physics 2015-03-26 Hassan Amirhashchi

In this paper, we have considered a spatially flat FRW universe filled with pressureless matter and dark energy. We have considered a phenomenological parametrization of the deceleration parameter $q(z)$ and from this we have reconstructed…

General Relativity and Quantum Cosmology · Physics 2017-03-22 Abdulla Al Mamon , Sudipta Das

Understanding the accelerating expansion of the Universe remains a fundamental challenge in modern cosmology. In this paper, we investigate a cosmological model parametrized by a generalized variable deceleration parameter to elucidate the…

General Relativity and Quantum Cosmology · Physics 2023-09-29 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , F. Awad , M. Bennai

We explore the late time cosmological dynamics of the Universe within the framework of $f(Q,\mathcal{L}_{m})$ gravity by considering the specific form $f(Q, \mathcal{L}_m)=-Q+2\mathcal{L}_m+\gamma$. To describe the cosmic pressure…

General Relativity and Quantum Cosmology · Physics 2025-08-08 Amit Samaddar , S. Surendra Singh

In the current work, we have implemented an extension of the standard Gaussian Process formalism, namely the Multi-Task Gaussian Process with the ability to perform a joint learning of several cosmological data simultaneously. We have…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-15 Balakrishna S. Haridasu , Vladimir V. Luković , Michele Moresco , Nicola Vittorio