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Related papers: $Om$ Diagnostic for Dilaton Dark Energy

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We examine the validity of the $\Lambda$CDM model, and probe for the dynamics of dark energy using latest astronomical observations. Using the $Om(z)$ diagnosis, we find that different kinds of observational data are in tension within the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Yuecheng Zhang , Hanyu Zhang , Dandan Wang , Yanghan Qi , Yuting Wang , Gong-Bo Zhao

We introduce two new diagnostics of dark energy (DE). The first, Om, is a combination of the Hubble parameter and the cosmological redshift and provides a "null test" of dark energy being a cosmological constant. Namely, if the value of…

Astrophysics · Physics 2008-11-26 Varun Sahni , Arman Shafieloo , Alexei A. Starobinsky

$Om(z)$ is a diagnostic approach to distinguish dark energy models. However, there are few articles to discuss what is the distinguishing criterion. In this paper, firstly we smooth the latest observational $H(z)$ data using a…

General Relativity and Quantum Cosmology · Physics 2016-06-13 Jing-Zhao Qi , Ming-Jian Zhang , Wen-Biao Liu

We apply the $Om$ diagnostic to models for dark energy based on scalar fields. In case of the power law potentials, we demonstrate the possibility of slowing down the expansion of the Universe around the present epoch for a specific range…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-11 M. Shahalam , Sasha Sami , Abhineet Agarwal

Recent DESI data suggest that dark energy may be evolving and motivate the use of model-independent diagnostics such as $Om(z)$ and probes of the equation of state (EoS) of dark energy, $w(z)$. Traditional reconstructions of $w(z)$ rely on…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-27 Satadru Bag , Ryan E. Keeley , Varun Sahni , Arman Shafieloo

Statefinder diagnostic is a useful method which can differ one dark energy model from each others. In this letter, we apply this method to a holographic dark energy model from Ricci scalar curvature, called the Ricci dark energy model(RDE).…

High Energy Physics - Theory · Physics 2008-12-18 Chao-Jun Feng

In this paper, we propose a new parametrization of dark energy based on the $Om(z)$ diagnostic tool behavior. For this purpose, we investigate a functional form of the $Om(z)$ that predicts the popular dark energy dynamical models, namely…

General Relativity and Quantum Cosmology · Physics 2023-07-13 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

One of the most important questions nowadays in physics concerns the nature of the so-called dark energy. It is also a consensus among cosmologists that such a question will not be answered on the basis only of observational data. However,…

Astrophysics · Physics 2008-11-26 Deepak Jain , J. S. Alcaniz , Abha Dev

Cosmic acceleration is usually related with the unknown dark energy, which equation of state, w(z), is constrained and numerically confronted with independent astrophysical data. In order to make a diagnostic of w(z), the introduction of a…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Celia Escamilla-Rivera , Julio C. Fabris

A new diagnostic method, $Om$ is applied to generalized Chaplygin gas (GCG) model as the unification of dark matter and dark energy. On the basis of the recently observed data: the Union supernovae, the observational Hubble data, the SDSS…

Astrophysics · Physics 2010-11-02 Jianbo Lu , Lixin Xu

Investigations on dark energy (DE) are currently inconclusive about its time evolution. Hints of this possibility do however glow now and then in the horizon. Herein we assess the current status of dynamical dark energy (DDE) in the light…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-06 Joan Sola Peracaula , Adria Gomez-Valent , Javier de Cruz Perez

Geometrical diagnostic, involving the statefinder $\{r,s\}$ and $Om(x)$, is widely used to discriminate different dark energy models. We apply the statefinder $\{r,s\}$ and $Om(x)$ to purely kinetic k-essence dark energy model with…

General Relativity and Quantum Cosmology · Physics 2010-04-30 Xiang-Ting Gao , Rong-Jia Yang

Cosmological models with different types of Dark Energy are becoming viable alternatives for standard models with the cosmological constant. Yet, such models are more difficult to analyze and to simulate. We present analytical…

Astrophysics · Physics 2009-11-07 R. Mainini , A. V. Maccio' , S. A. Bonometto , A. Klypin

Using various latest cosmological datasets including Type-Ia supernovae, cosmic microwave background radiation, baryon acoustic oscillations, and estimations of the Hubble parameter, we test some dark energy models with parameterized…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-28 Jing Yang , Xin-Yan Fan , Chao-Jun Feng , Xiang-Hua Zhai

We use high-resolution simulations of large-scale structure formation to analyze the effects of interacting dark matter and dark energy on the evolution of the halo mass function. Using a chi-square likelihood analysis, we find significant…

Astrophysics · Physics 2009-11-13 P. M. Sutter , P. M. Ricker

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

Recent observations from the Dark Energy Spectroscopic Instrument (DESI) Data Release 2 (DR2) have revealed compelling evidence for dynamical dark energy, challenging the $\Lambda$CDM paradigm. In this work, we adopt a data-driven,…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-05 Changyu You , Dan Wang , Tao Yang

This manuscript presents a diagnostic analysis of three dark energy models resulting from the parametrization of the deceleration parameter. These models exhibit intriguing features, including late-time acceleration and a cosmological phase…

General Relativity and Quantum Cosmology · Physics 2024-08-12 Dhruv Arora , Himanshu Chaudhary , Shibesh Kumar Jas Pacif , G. Mustafa

We study properties of dark matter halos in a variety of models which include Dark Energy (DE). We consider both DE due to a scalar field self--interacting through Ratra-Peebles or SUGRA potentials, and DE with constant negative w=p\rho…

Astrophysics · Physics 2009-11-07 A. Klypin , A. V. Maccio' , R. Mainini , S. A. Bonometto

In the present work, we perform a comparative study of different interacting dark energy (DE) models using the Statefinder diagnostics. In particular, 17 different forms of the energy transfer rate $Q$ between DE and dark matter (DM) were…

General Relativity and Quantum Cosmology · Physics 2023-10-09 Raul Carrasco , Angel Rincon , Joel Saavedra , Nelson Videla
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