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The dynamical aspect of accelerating cosmological model has been studied in this paper in the context of modified symmetric teleparallel gravity, the $f(Q)$ gravity. Initially, we have derived the dynamical parameters for two well known…

General Relativity and Quantum Cosmology · Physics 2023-07-18 S. A. Narawade , Shashank P. Singh , B. Mishra

In this study, we explore the impact of various combinations of CMB-independent datasets, including the recent DESI BAO measurements, on the equation of state (EoS) of dark energy and other cosmological parameters within the framework of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-13 Manisg Yadav , Archana Dixit , M. S. Barak , Anirudh Pradhan

A new phenomenological dark energy model, originally associated to the large-scale structure formation and considered as a solution to the fine-tuning and coincidence problems related to the cosmological constant, was analyzed within the…

General Relativity and Quantum Cosmology · Physics 2026-03-05 A. Kazım Çamlıbel

Most parameterizations of the dark energy equation of state do not reflect realistic underlying physical models. Here, we develop a relatively simple description of dark energy based on the dynamics of a scalar field which is exact in the…

Astrophysics · Physics 2008-11-26 Robert Crittenden , Elisabetta Majerotto , Federico Piazza

We generalize the holographic dark energy model described in Hubble length IR cutoff by assuming a slowly time varying function for holographic parameter $c^2$. We calculate the evolution of EoS parameter and the deceleration parameter as…

General Relativity and Quantum Cosmology · Physics 2015-06-11 M. Malekjani

We use a parameterized equation of state (EOS) of dark energy to a 5D Ricci-flat cosmological solution and suppose the universe contains two major components: dark matter and dark energy. Using the recent observational datasets: the latest…

Astrophysics · Physics 2009-06-23 Chengwu Zhang , Lixin Xu , Yongli Ping , Hongya Liu

One of the important parameters in cosmology is the parameter characterizing the equation of state (EoS) of the sources driving the cosmic expansion. Epochs that are dominated by radiation, matter, or scalar fields, whether they are probed…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-16 Pankaj Saha , Sampurn Anand , L. Sriramkumar

We discuss the constraints on the time-varying equation of state for dark energy and the curvature of the universe using observations of type Ia supernovae from Riess et al. and the most recent Supernova Legacy Survey (SNLS), the baryon…

Astrophysics · Physics 2009-11-13 Kazuhide Ichikawa , Tomo Takahashi

Two new one-parameter tracking behavior dark energy representations $\omega=\omega_0/(1+z)$ and $\omega=\omega_0 e^{z/(1+z)}/(1+z)$ are used to probe the geometry of the Universe and the property of dark energy. The combined type Ia…

Astrophysics · Physics 2009-11-10 Yungui Gong , Yuan-Zhong Zhang

While modelling our late time cosmically accelerated universe, it is popular to involve different dark energy models, the equation of state of which can be taken as a function of the redshift and some unknown parameters. Barboza and Alcaniz…

General Physics · Physics 2019-09-25 Swetalina Bhowmik , Ritabrata Biswas

We investigate several phenomenological dark energy parameterizations using a joint analysis of late-time cosmological observations, including cosmic-chromatometer measurements of the Hubble parameter, DESI DR2 baryon acoustic oscillation…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-08 Chanchal Kumari , Dinesh Kumar

Some new exact solutions of Einstein's field equations have come forth within the scope of a spatially homogeneous and anisotropic Bianchi type-III space-time filled with barotropic fluid and dark energy by considering a variable…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-20 Hassan Amirhashchi , Anirudh Pradhan , Rekha Jaiswal

The question of correlations among empirical equation of state (EoS) parameters constrained by nuclear observables is addressed in a fully empirical meta-modeling approach. A recently proposed meta-modeling for the nuclear EoS in nuclear…

Nuclear Theory · Physics 2017-12-27 D. Chatterjee , F. Gulminelli , Ad. R. Raduta , J. Margueron

We propose the unified description of the early acceleration (cosmological inflation) and the present epoch of so called "dark energy". The inflation can be described by cosmic fluid with van der Waals equation of state and with viscosity…

General Relativity and Quantum Cosmology · Physics 2022-01-19 A. V. Astashenok , S. D. Odintsov , A. S. Tepliakov

In this work, we explore dark energy models, mainly ghost, generalized ghost, and generalized ghost pilgrim dark energy models within the framework of fractal cosmology. To obtain solutions for the field equations, we employ a…

General Relativity and Quantum Cosmology · Physics 2024-12-20 S. R. Bhoyar , Yash B. Ingole , A. P. Kale

Abandoning the perfect fluid hypothesis, we investigate here the possibility that the dark energy equation of state (EoS) $w$ is a nonlinear function of the energy density $\rho$. To this aim, we consider four different EoS describing…

Astrophysics · Physics 2009-11-13 V. F. Cardone , C. Tortora , A. Troisi , S. Capozziello

We use the newly released 182 Type Ia supernova data combined with the third-year Wilkinson Microwave Anisotropic Probe data (WMAP3) and large scale structure (LSS) information including SDSS and 2dFGRS to constrain the dark energy equation…

A huge amount of good quality astrophysical data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision…

Astrophysics · Physics 2009-06-23 S. Capozziello

Within the scope of an anisotropic Bianchi type-VI cosmological model we have studied the evolution of the universe filled with perfect fluid and dark energy. To get the deterministic model of Universe, we assume that the shear scalar…

General Relativity and Quantum Cosmology · Physics 2015-05-01 Bijan Saha

We study two transition periods in cosmology: radiation-to-matter and matter-to-dark energy. In each case, we define a new parameter $\chi$ given by the ratios of the two energy densities involved in the transition. Our study of the second…

General Relativity and Quantum Cosmology · Physics 2024-06-05 Bob Osano