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We study how the determination of the Hubble constant from cosmological distance measures is affected by models of dark energy and vice versa. For this purpose, constraints on the Hubble constant and dark energy are investigated using the…

Astrophysics · Physics 2008-11-26 Kazuhide Ichikawa , Tomo Takahashi

In modern cosmology, the discovery of the universe's accelerated expansion has significantly transformed our understanding of cosmic evolution and expansion history. The unknown properties of dark energy, the driver of this acceleration,…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Xincheng Zhu , Rui Xu , Dandan Xu

The mass function of cluster-size halos and their redshift distribution are computed for 12 distinct accelerating cosmological scenarios and confronted to the predictions of the conventional flat $\Lambda$CDM model. The comparison with…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-27 S. Basilakos , M. Plionis , J. A. S. Lima

Reconstructing the evolution history of the dark energy equation of state parameter $w(z)$ directly from observational data is highly valuable in cosmology, since it contains substantial clues in understanding the nature of the accelerated…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Zhi-E Liu , Hao-Ran Yu , Tong-Jie Zhang , Yan-Ke Tang

Models of dark energy or modified gravity that tries to alleviate the tensions on the Hubble constant ($H_0$) and the matter fluctuation parameter ($\sigma_8$) are usually parameterized as function of either late or early time cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-05 Ziad Sakr

The matter bounce scenario allows for a sizable parameter space where cosmological fluctuations originally exited the Hubble radius when the background energy density was small. In this scenario and its extended versions, the low energy…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 Yi-Fu Cai , Francis Duplessis , Damien A. Easson , Dong-Gang Wang

We examine the dark energy and matter densities allowed by precision measurements of distances out to various redshifts, in the presence of spatial curvature and (near) arbitrary behavior of the dark energy equation of state. Degeneracies…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-22 Arman Shafieloo , Eric V. Linder

Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature-redshift scaling relation. We use the most…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Ivan de Martino

The Hubble tension and attempts to resolve it by modifying the physics of (or at) recombination motivate finding ways to determine $H_0$ and the sound horizon at the epoch of baryon decoupling $r_{\rm d}$ in ways that neither rely on a…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-26 Levon Pogosian , Gong-Bo Zhao , Karsten Jedamzik

Cosmological tensions in current times have opened a wide door to study new probes to constrain cosmological parameters, specifically, to determine the value of the Hubble constant $H_0$ through independent techniques. The two standard…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Celia Escamilla-Rivera , Rubén Torres Castillejos

The tension between the Hubble constant obtained from the local measurements and from cosmic microwave background (CMB) measurements motivated us to consider the cosmological model beyond $\Lambda$CDM one. We investigate the cosmology in…

General Relativity and Quantum Cosmology · Physics 2022-06-15 Jing Li , Yongxiang Zhou , Xun Xue

We investigate a phenomenological extension of the standard $\Lambda$CDM framework, the $\Omega_1\Omega_2$-$\Lambda$CDM model, in which the total energy density of the universe is expanded in powers of $1+z$. This parameterization recovers…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Suresh Kumar

The $\Lambda$ cold dark matter ($\Lambda$CDM) cosmological model provides a good description of a wide range of astrophysical and cosmological observations. However, severe challenges to the phenomenological $\Lambda$CDM model have emerged…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-10 X. D. Jia , J. P. Hu , D. H. Gao , S. X. Yi , F. Y. Wang

In the context of the new standard LambdaCDM cosmology we resolve conflicts in the literature regarding fundamental aspects of the expansion of the universe and cosmic horizons and we link these concepts to observational tests. We derive…

Astrophysics · Physics 2007-05-23 Tamara M. Davis

Standard cosmology has long been plagued by a number of persistent problems. The origin of the apparent acceleration of the cosmic expansion remains enigmatic. The cosmological constant has been reintroduced as a free parameter with a value…

General Physics · Physics 2023-02-28 Jan O. Stenflo

Imagine a scenario in which the dark energy forms via the condensation of dark matter at some low redshift. The Compton wavelength therefore changes from small to very large at the transition, unlike quintessence or metamorphosis. We study…

Astrophysics · Physics 2009-11-07 Bruce A. Bassett , Martin Kunz , David Parkinson , Carlo Ungarelli

The Hubble tension has become one of the central problems in cosmology. In this work, we determine the Hubble constant $H_0$ and sound horizon $r_d$ by using the combination of Baryon Acoustic Oscillations (BAOs) from DESI surveys,…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-06 Zhiwei Yang , Tonghua Liu , Xiaolei Li

We have witnessed different values of the Hubble constant being found in the literature in the past years. Albeit, early measurements often result in an $H_0$ much smaller than those from late-time ones, producing a statistically…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-11 Simony S da Costa , Dêivid R da Silva , Álvaro S de Jesus , Nelson Pinto-Neto , Farinaldo S Queiroz

The Hubble-Lemaitre tension is currently one of the most important questions in cosmology. Most of the focus so far has been on reconciling the Hubble constant value inferred from detailed cosmic microwave background measurement with that…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-29 Kylar L. Greene , Francis-Yan Cyr-Racine

Magnitude predictions of $\Lambda$CDM, as parametrized by the Planck collaboration, are not consistent with the supernova data of the whole Pantheon+ sample even when, in order to take into account the uncertainty about its value, the…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-03 Yves-Henri Sanejouand
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