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In this paper, we propose a new pressure parametric model of the total cosmos energy components in a spatially flat Friedmann-Robertson-Walker (FRW) universe and then reconstruct the model into quintessence and phantom scenarios,…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-14 Jun-Chao Wang , Xin-He Meng

Using only the standard considerations of spacetime foam and the Euclidean Quantum Gravity techniques known long ago, we result to a model of Topological Dark Energy (TDE) that outperforms the standard $\Lambda$CDM paradigm with regard to…

General Relativity and Quantum Cosmology · Physics 2025-07-25 Fotios K. Anagnostopoulos , Stylianos A. Tsilioukas , Emmanuel N. Saridakis

Observations of high redshift supernovae imply an accelerating Universe which can only be explained by an unusual energy component such as vacuum energy or quintessence. To assess the ability of current and future supernova data to…

Astrophysics · Physics 2009-11-06 Yun Wang , Peter M. Garnavich

Although today there are many observational methods, Type Ia supernovae (SNIa) is still one of the most powerful tools to probe the mysterious dark energy (DE). The most recent SNIa datasets are the 307 SNIa "Union" dataset \cite{kow08} and…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-10 Miao Li , Xiao-Dong Li , Shuang Wang

Aiming at exploring the nature of dark energy (DE), we use forty-three observational Hubble parameter data (OHD) in the redshift range $0 < z \leqslant 2.36$ to make a cosmological model-independent test of the $\Lambda$CDM model with…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-13 Shu-Lei Cao , Xiao-Wei Duan , Xiao-Lei Meng , Tong-Jie Zhang

In this article, we investigate a new parametrization of the dark energy equation of state (EoS) with a single parameter for a barotropic fluid that deviates from the standard $\Lambda$CDM cosmology. We derive observational constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 D. Revanth Kumar , Santosh Kumar Yadav

We propose a novel dark-energy equation-of-state parametrization, with a single parameter $\eta$ that quantifies the deviation from $\Lambda$CDM cosmology. We first confront the scenario with various datasets, from Hubble function (OHD),…

General Relativity and Quantum Cosmology · Physics 2024-06-04 J. K. Singh , Preeti Singh , Emmanuel N. Saridakis , Shynaray Myrzakul , Harshna Balhara

We reconstruct the expansion history of the Universe using type Ia supernovae (SN Ia) in a manner independent of any cosmological model assumptions. To do so, we implement a non-parametric iterative smoothing method on the Joint Light-curve…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-12 Hanwool Koo , Arman Shafieloo , Ryan E. Keeley , Benjamin L'Huillier

In the context of a spatially flat $\Lambda(t)$CDM cosmology, we investigate interacting dark energy (IDE) scenarios characterized by phenomenological interaction terms proportional to the Hubble expansion rate and the dark energy density.…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-13 A. A. Escobal , H. A. P. Macedo , J. F. Jesus , R. C. Nunes , J. A. S. Lima

We constrain and compare the $w_{0}w_{a}$CDM dynamical dark energy model and three $f(R)$ modified gravity models using the current cosmological distance measurements, including 112 high-quality localized FRBs, BAO measurements from the…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-24 Shuai Feng , Yan Gong , Xiaohui Liu , Jun-Hui Yan , Xuelei Chen

We analyze how predictions of cosmological models depend on a choice of described observational data, restrictions on flatness, and how this choice can alleviate the $H_0$ tension. These effects are demonstrated in the $w$CDM model in…

General Relativity and Quantum Cosmology · Physics 2020-02-11 G. S. Sharov , E. S. Sinyakov

The decaying vacuum model (DV), treating dark energy as a varying vacuum, has been studied well recently. The vacuum energy decays linearly with the Hubble parameter in the late-times, $\rho_\Lambda(t) \propto H(t)$, and produces the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. L. Tong , H. Noh

In this note, we consider the observational constraints on some cosmological models by using the 307 Union type Ia supernovae (SNIa), the 32 calibrated Gamma-Ray Bursts (GRBs) at $z>1.4$, the updated shift parameter $R$ from WMAP 5-year…

Astrophysics · Physics 2009-03-23 Hao Wei

We apply the Statefinder hierarchy and the growth rate of matter perturbations to discriminate modified Chaplygin gas (MCG), generalized Chaplygin gas (GCG), superfluid Chaplygin gas (SCG), purely kinetic k-essence (PKK), and $\Lambda$CDM…

General Relativity and Quantum Cosmology · Physics 2014-12-30 Jun Li , Rong-Jia Yang , Bohai Chen

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 present a detailed and pedagogical analysis of recent cosmological data, including CMB, BAO, SnIa and the recent local measurement of $H_0$. We thus obtain constraints on the parameters of standard dark energy parameterizations,…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-15 Anastasios Theodoropoulos , Leandros Perivolaropoulos

We use 21 Hubble parameter versus redshift data points, from Gazta\~{n}aga et al. (2009), Stern et al. (2010), and Moresco et al. (2012), to place constraints on model parameters of constant and time-evolving dark energy cosmologies. This…

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

Type Ia supernova (SN Ia), galaxy clustering, and cosmic microwave background anisotropy (CMB) data provide complementary constraints on the nature of the dark energy in the universe. We find that the three-year Wilkinson Microwave…

Astrophysics · Physics 2010-11-11 Yun Wang , Pia Mukherjee

This study investigates and compares two prominent two-dimensional dark energy (DE) parameterizations: Barboza-Alcaniz (BA) and Logarithmic forms by comparing them with a comprehensive set of observational data comprising Type Ia Supernovae…

General Physics · Physics 2026-02-11 Archana Dixit , Saurabh Verma , Anirudh Pradhan , M. S. Barak

Observational constraints are considered on a $w_{log}$CDM model of the dark energy equation of state, $w_{d}(z) = w_{0} + w_{a}\left( \frac{\ln(2+z)}{1+z} - \ln 2 \right)$, using the most recent cosmological datasets including DESI Baryon…

General Physics · Physics 2026-03-10 Saurabh Verma , Archana Dixit , Anirudh Pradhan , M. S. Barak