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We provide a model-independent reconstruction of dark energy from $z=0$ to $ \gtrsim 10^5$. We parameterise the model by a perfect fluid with a series of physically well-motivated bins in energy-density, such that the equation of state is…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-01 Adam Moss , Edmund Copeland , Steven Bamford , Thomas Clarke

Observational data play a pivotal role in identifying cosmological models that are both theoretically consistent and empirically viable. In this work, we investigate the level of preference for dynamical dark energy over a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-21 Himanshu Chaudhary , Vipin Kumar Sharma , Salvatore Capozziello , G. Mustafa

Combined measurements of Baryon Acoustic Oscillations (BAO) from the Dark Energy Spectroscopic Survey (DESI), the Cosmic Microwave Background (CMB) and Type Ia Supernovae (SN Ia), have recently challenged the $\Lambda$-Cold Dark Matter…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-10 Rayff de Souza , Agripino Sousa-Neto , Javier E. González , Jailson Alcaniz

In this work, we have studied the logarithmic entropy corrected holographic dark energy (LECHDE) model with Granda-Oliveros (G-O) IR cutoff. The evolution of dark energy (DE) density $\Omega'_D$, the deceleration parameter, $q$, and…

General Relativity and Quantum Cosmology · Physics 2013-05-21 A. Khodam-Mohammadi , Antonio Pasqua , M. Malekjani , Iuliia Khomenko , M. Monshizadeh

(Abridged) Tests that have been proposed to differentiate among dark energy (DE) models are based on observations of galaxies at high redshift (z>0), to be obtained in the future. We suggest here a new test that is valid at z\simeq 0. It is…

Astrophysics · Physics 2008-01-05 R. Opher , A. Pelinson

In this work, we propose a non-standard dark matter (NSDM) model in which the equation of state (EoS) of dark matter (DM) is parameterized as $w_{\rm dm} = w_2 a^2$, and this DM model is motivated by the idea that DM must become cold dark…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Yan-Hong Yao , Yi-Hao Shen , Tian-Nuo Li , Guo-Hong Du , Yungui Gong

Although $\Lambda$CDM model is very successful in many aspects, it has been seriously challenged. Recently, warm dark matter (WDM) remarkably rose as an alternative of cold dark matter (CDM). In the literature, many attempts have been made…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Hao Wei , Zu-Cheng Chen , Jing Liu

Reconstructed from lensing tomography, the evolution of the dark matter density field in the well-understood linear regime can provide model-independent constraints on the growth function of structure and the evolution of the dark energy…

Astrophysics · Physics 2008-11-26 Wayne Hu

We explore the properties of dark energy from recent observational data, including the Gold Sne Ia, the baryonic acoustic oscillation peak from SDSS, the CMB shift parameter from WMAP3, the X-ray gas mass fraction in cluster and the Hubble…

Astrophysics · Physics 2008-11-26 Puxun Wu , Hongwei Yu

We study the dynamical properties of dark energy based on a large family of PADE parameterizations for which the dark energy density evolves as a ratio between two polynomials in the scale factor of the universe. Using the latest…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-14 A. Mehrabi , S. Basilakos

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

We investigate the interacting dark energy models by using the diagnostics of statefinder hierarchy and growth rate of structure. We wish to explore the deviations from $\Lambda$CDM and to differentiate possible degeneracies in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-10 Jing-Lei Cui , Lu Yin , Ling-Feng Wang , Yun-He Li , Xin Zhang

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

We investigate potential deviations from cold dark matter (CDM) using the latest Baryon Acoustic Oscillations (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI). Analyzing DESI data alone constrains the dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-22 Utkarsh Kumar , Abhijith Ajith , Amresh Verma

Dark Energy Spectroscopic Instrument (DESI) observations, when combined with Cosmic Microwave Background (CMB) and Type Ia supernovae (SNe), have led to statistically significant dynamical dark energy (DDE) claims. In this letter we…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-28 Eoin Ó Colgáin , M. M. Sheikh-Jabbari

Recently, a new dark energy model called $\Lambda$HDE was proposed. In this model, dark energy consists of two parts: cosmological constant $\Lambda$ and holographic dark energy (HDE). Two key parameters of this model are the fractional…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-14 Lanjun Zhou , Shuang Wang

We investigate the dynamical properties of dark energy through a detailed analysis of its equation of state parameter $w(z)$ as a function of redshift. We derive a general expression for $w(z)$ from the Friedmann-Lema\^itre-Robertson-Walker…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-29 J. W. Moffat , E. J. Thompson

The canonical cosmological constant dominated cold dark matter model (LCDM) may possess too much power on small scales at z=0, manifested as central over-concentration of dark matter and over-abundance of dwarf galaxies. We suggest an…

Astrophysics · Physics 2009-10-31 Renyue Cen

We derive multiple constraints on dark energy and compare dynamical dark energy models with a time-varying equation of state ($w_0 w_a$CDM) versus a cosmological constant model ($\Lambda$CDM). We use Baryon Acoustic Oscillation (BAO) from…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-24 Mustapha Ishak , Leonel Medina-Varela

In this work, we perform a comprehensive joint analysis of three representative dark energy models - ${\rm{\Lambda}CDM}$, the Chevallier-Polarski-Linder (CPL) parametrization, and the Generalised Emergent Dark Energy (GEDE) model - using…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-10 Tonghua Liu , Xiaolei Li , Jieci Wang