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Related papers: Two new diagnostics of dark energy

200 papers

While cold dark matter is widely supported by a range of cosmological observations, it encounters several difficulties at smaller scales. These issues have prompted the investigation of various alternative dark matter candidates, leaving…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Jian-Qi Liu , Yan-Hong Yao , Yan Su , Jia-Wei Wu

A cosmological constant, Lambda, is the most natural candidate to explain the origin of the dark energy (DE) component in the Universe. However, due to experimental evidence that the equation of state (EOS) of the DE could be evolving with…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Joan Sola , Hrvoje Stefancic

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

I briefly review our current understanding of dark matter and dark energy. The first part of this paper focusses on issues pertaining to dark matter including observational evidence for its existence, current constraints and the `abundance…

Astrophysics · Physics 2022-07-19 Varun Sahni

The property of dark energy and the physical reason for acceleration of the present universe are two of the most difficult problems in modern cosmology. The dark energy contributes about two-thirds of the critical density of the present…

Astrophysics · Physics 2009-11-13 F. Y. Wang , Z. G. Dai

Cosmic microwave background data from the {\it Planck} satellite, combined with baryon acoustic oscillation measurements from the Dark Energy Spectroscopic Instrument and Type Ia supernovae from various samples, provide hints of dynamical…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-09 Adrià Gómez-Valent , Alex González-Fuentes

The accelerating expansion of the universe is the most surprising cosmological discovery in many decades. In this short review, we briefly summarize theories for the origin of cosmic acceleration and the observational methods being used to…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-03 Michael J. Mortonson , David H. Weinberg , Martin White

This study investigates the cosmological implications of $f(R,\Sigma,T)$ gravity by reconstructing the Hubble parameter from a logarithmic parameterization of the $O_m(z)$ diagnostic. Our approach offers a model-independent way to probe the…

General Relativity and Quantum Cosmology · Physics 2026-05-12 N. Myrzakulov , Anirudh Pradhan , Anil Kumar Yadav , S. H. Shekh

The main aim of this work is to use a model-independent approach, along with late-time observational probes, to reconstruct the dark energy (DE) equation of state $w_{\rm DE}(z)$. Our analysis showed that, for a late time universe, $w_{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-23 Luis A. Escamilla , Supriya Pan , Eleonora Di Valentino , Andronikos Paliathanasis , J. Alberto Vázquez , Weiqiang Yang

The new 182 gold supernova Ia data, the baryon acoustic oscillation measurement and the shift parameter determined from the Sloan Digital Sky Survey and the three-year Wilkinson Microwave Anisotropy Probe data are combined to reconstruct…

Astrophysics · Physics 2008-11-26 Yungui Gong , Anzhong Wang

Early dark energy (EDE) that behaves like a cosmological constant at early times (redshifts $z\gtrsim3000$) and then dilutes away like radiation or faster at later times can solve the Hubble tension. In these models, the sound horizon at…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-12 Vivian Poulin , Tristan L. Smith , Tanvi Karwal , Marc Kamionkowski

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

The $Om3$ diagnostic (Shafieloo et al. 2012) tests the consistency of the cosmological constant as a candidate for dark energy using Baryon Acoustic Oscillation (BAO) data. An important feature of $Om3$ is that it is independent of any…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-12 Arman Shafieloo , Sangwoo Park , Varun Sahni , Alexei A. Starobinsky

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

$Om(z)$ 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

Phenomena currently attributed to Dark Energy (DE) and Dark Matter (DM) are merely a result of the interplay between gravitational energy density, generated by the contraction of space by matter, and the energy density of the Cosmological…

Astrophysics · Physics 2008-12-25 Shlomo Barak , Elia M Leibowitz

Aiming at exploring the nature of dark energy, we use thirty-six observational Hubble parameter data (OHD) in the redshift range $0 \leqslant z \leqslant 2.36$ to make a cosmological model-independent test of the two-point…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-10 Xiao-Lei Meng , Xin Wang , Shi-Yu Li , Tong-Jie Zhang

Determining the mechanism behind the current cosmic acceleration constitutes a major question nowadays in theoretical physics. If the dark energy route is taken, this problem may potentially bring to light new insights not only in Cosmology…

Astrophysics · Physics 2009-07-09 E. M. Barboza , J. S. Alcaniz

The cosmological constant and many other possible origins for acceleration of the cosmic expansion possess variations in the dark energy properties slow on the Hubble time scale. Given that models with more rapid variation, or even phase…

Astrophysics · Physics 2009-08-21 Eric V. Linder

The standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the Hubble constant $H_{0}$ and inferences of its values from Cosmic Microwave Background (CMB) anisotropies.…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-05 K. Rezazadeh , A. Ashoorioon , D. Grin