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Related papers: Early Dark Energy Cosmologies

200 papers

We use a combination of the most recent cosmic microwave background (CMB) flat -band power measurements to place constraints on Hubble's constant h and the total density of the Universe Omega_o in the context of inflation-based cold dark…

Astrophysics · Physics 2009-10-30 Charles H. Lineweaver , Domingos Barbosa

Astrophysical tests of the stability of fundamental couplings, such as the fine-structure constant $\alpha$, are a powerful probe of new physics. Recently these measurements, combined with local atomic clock tests and Type Ia supernova and…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-13 C. J. A. P. Martins , A. M. M. Pinho , P. Carreira , A. Gusart , J. López , C. I. S. A. Rocha

In this work, we explore the possibility that Early Dark Energy (EDE) is dynamical in nature and study its effect on cosmological observables. We introduce a parameterization of the equation of state allowing for an equation of state $w$…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-04 Ravi Kumar Sharma , Subinoy Das , Vivian Poulin

Based on the latest MLCS17 SNe Ia data provided by Hicken et al. (2009), together with the Baryon Acoustic Oscillation (BAO) and strong gravitational lenses (SGL), we investigate the dark energy equation-of-state parameter for both constant…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-04 Qing-Jun Zhang , Yue-Liang Wu

A significant observational effort has been directed to unveil the nature of the so-called dark energy. However, given the large number of theoretical possibilities, it is possible that such a task cannot be performed on the basis only of…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-12 R. Silva , R. S. Goncalves , J. S. Alcaniz , H. H. B. Silva

In this work, we study a class of early dark energy (EDE) models, in which, unlike in standard DE models, a substantial amount of DE exists in the matter-dominated era, self-consistently including DE perturbations. Our analysis shows that,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Ujjaini Alam

By studying the present cosmological data, particularly on CMB, SNeIA and LSS, we find that the future fate of the universe, for simple linear models of the dark energy equation-of-state, can vary between the extremes of (I) a divergence of…

Astrophysics · Physics 2009-11-10 Paul H. Frampton

We use Hubble parameter versus redshift data from Stern, et al(2010) and Gazta\~{n}aga, et al (2009) to place constraints on model parameters of constant and time-evolving dark energy cosmological models. These constraints are consistent…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-12 Yun Chen , Bharat Ratra

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

Dark energy can be studied by its influence on the expansion of the Universe as well as on the growth history of the large-scale structure. In this paper, we follow the growth of the cosmic density field in early dark energy cosmologies by…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Lukas Hollenstein , Domenico Sapone , Robert Crittenden , Bjoern Malte Schaefer

We constrain cosmological parameters using only Hubble parameter data and quantify the impact of future Hubble parameter measurements on parameter estimation for the most typical dark energy models. We first constrain cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-27 Jia-Jia Geng , Rui-Yun Guo , Anzhong Wang , Jing-Fei Zhang , Xin Zhang

Following the holographic principle, which suggests that the energy density of dark energy may be proportional inversely to the area of the event horizon of the Universe, we have proposed a new energy density of dark energy through the…

General Relativity and Quantum Cosmology · Physics 2023-01-25 H. R. Fazlollahi

We provide preliminary quantitative evidence that a new solution to averaging the observed inhomogeneous structure of matter in the universe [gr-qc/0702082, arxiv:0709.0732], may lead to an observationally viable cosmology without exotic…

Astrophysics · Physics 2008-11-26 Ben M. Leith , S. C. Cindy Ng , David L. Wiltshire

Early Dark Energy (EDE) contributing a fraction $f_{\rm EDE}(z_c)\sim 10 \%$ of the energy density of the universe around $z_c\simeq 3500$ and diluting as or faster than radiation afterwards, can provide a resolution to the Hubble tension,…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-04 Riccardo Murgia , Guillermo F. Abellán , Vivian Poulin

We present cosmological constraints arising from the first measurement of the radial (line-of-sight) baryon acoustic oscillations (BAO) scale in the large scale structure traced by the galaxy distribution. Here we use these radial BAO…

Astrophysics · Physics 2009-09-02 Enrique Gaztanaga , Ramon Miquel , Eusebio Sanchez

Recent data advances offer the exciting prospect of a first look at whether dark energy has a dynamical equation of state or not. While formally theories exist with a constant equation of state, they are nongeneric -- Einstein's…

Astrophysics · Physics 2009-11-10 Eric V. Linder , Ramon Miquel

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

In this work, we have proposed a general dark energy density parametrization to study the evolution of the universe. We have also constrained the model parameters using the combination of Type Ia supernova (SNIa), baryonic acoustic…

General Relativity and Quantum Cosmology · Physics 2018-07-25 Abdulla Al Mamon

A simple speed-up cosmology model is proposed to account for the dark energy puzzle. We condense contributions from dark energy and curvature term into one effective parameter in order to reduce parameter degeneracies and to find any…

Astrophysics · Physics 2007-10-10 Xin-He Meng , Meng Su , Zheng Wang

The nature of dark energy can be probed not only through its equation of state, but also through its microphysics, characterized by the sound speed of perturbations to the dark energy density and pressure. As the sound speed drops below the…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-25 Roland de Putter , Dragan Huterer , Eric V. Linder