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Related papers: A novel early Dark Energy model

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We study the dynamics of Friedmann-Lema\^itre-Robertson-Walker models where a dark energy component with a quadratic equation of state (EoS) nonlinearly interacts with cold dark matter. Thus, two energy scales naturally come into play:…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-06 Molly Burkmar , Marco Bruni , Thomas Waters

We investigate the bounds on the sum of neutrino masses in a cosmic-acceleration scenario where the equation of state $w(z)$ of dark energy (DE) is constructed in a model-independent way, using a basis of principal components (PCs) that are…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-11 Ana Diaz Rivero , V. Miranda , Cora Dvorkin

Dark energy is a fundamental constituent of our universe, its status in the cosmological field equation should be equivalent to that of gravity. Here we construct a dark energy and matter gravity coupling (DEMC) model of cosmology in a way…

General Physics · Physics 2015-01-14 Ti-Pei Li

A new bound dark energy, BDE, cosmology has been proposed where the dark energy is the binding energy between light meson fields that condense a few tens of years after the big bang. It is reported that the correct dark energy density…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-06 Rodger I. Thompson

It has been noted that with the pre-recombination early dark energy (EDE) resolution of Hubble tension, the preference of recent datasets for the evolving dark energy (DE) can be suppressed significantly. In this work, we clarify and…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-21 Hao Wang , Yun-Song Piao

Observational evidence suggests that our universe is presently dominated by a dark energy component and undergoing accelerated expansion. We recently introduced a model, motivated by string theory for short-distance physics, for explaining…

High Energy Physics - Theory · Physics 2009-11-07 M. Bastero-Gil , L. Mersini

The dark sector of the Universe need not be completely separable into distinct dark matter and dark energy components. We consider a model of early dark energy in which the dark energy mimics a dark matter component in both evolution and…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-05 Jannis Bielefeld , Robert R. Caldwell , Eric V. Linder

The $\Lambda$CDM model successfully explains a wide range of cosmological observations; however, persistent discrepancies most notably the $H_0$ tension between early and late time measurements challenge its completeness. No proposed…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 Upala Mukhopadhyay , Purba Mukherjee , Alexandre Tkatchenko

The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-17 Muhammad Omer Farooq

We compare the maximal abundance of massive systems predicted in different dynamical dark energy (DDE) models at high redshifts z = 4-7 with the measured abundance of the most massive galaxies observed to be already in place at such…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-27 N. Menci , A. Grazian , M. Castellano , P. Santini , E. Giallongo , A. Lamastra , F. Fortuni , A. Fontana , E. Merlin , T. Wang , D. Elbaz , N. G. Sanchez

Within the limits of the present cosmological observations in f(R,T) gravity theory, we have analyzed a spherically symmetric space-time in 5D setting. The field equations have been carefully studied considering reasonable cosmological…

General Relativity and Quantum Cosmology · Physics 2020-10-28 Pheiroijam Suranjoy Singh , Kangujam Priyokumar Singh

In this study, we use a flexible parametrization of the equation of state of dark energy to explore its possible evolution with datasets from the Dark Energy Spectroscopic Instrument (DESI), Planck cosmic microwave background, and either…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-14 Ryan E. Keeley , Kevork N. Abazajian , Manoj Kaplinghat , Arman Shafieloo

The presented paper is a comprehensive analysis of two dark energy (DE) cosmological models wherein exact solutions of the Einstein field equations (EFEs) are obtained in a model-independent way (or by cosmological parametrization). A…

General Physics · Physics 2022-07-20 S. K. J. Pacif

We propose and investigate a class of dynamical dark energy models in which the cosmological constant evolves from negative values in the early Universe to a positive value at low redshifts. This framework includes a generalised ladder-step…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Mariam Bouhmadi-López , Beñat Ibarra-Uriondo

We study the impact of early dark energy (EDE) cosmologies on galaxy properties by coupling high-resolution numerical simulations with semi-analytic modeling (SAM) of galaxy formation and evolution. EDE models are characterized by a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Fabio Fontanot , Volker Springel , Raul E. Angulo , Bruno Henriques

We propose a class of simple dark energy models which predict a late-time dark radiation component and a distinctive time-dependent equation of state $w(z)$ for redshift $z < 3$. The dark energy field can be coupled strongly enough to…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 Sourish Dutta , Stephen D. H. Hsu , Robert J. Scherrer

Two new one-parameter tracking behavior dark energy representations $\omega=\omega_0/(1+z)$ and $\omega=\omega_0 e^{z/(1+z)}/(1+z)$ are used to probe the geometry of the Universe and the property of dark energy. The combined type Ia…

Astrophysics · Physics 2009-11-10 Yungui Gong , Yuan-Zhong Zhang

We investigate the behaviour of dark energy using the recently released supernova data of Riess et al ~(2004) and a model independent parameterization for dark energy (DE). We find that, if no priors are imposed on $\Omega_{0m}$ and $h$, DE…

Astrophysics · Physics 2009-11-10 Ujjaini Alam , Varun Sahni , A. A. Starobinsky

Dark energy (DE) models with many free parameters are often considered excessive, as constraining all parameters poses a significant challenge. While such models offer greater flexibility to probe the DE sector in more detail. With the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Hanyu Cheng , Supriya Pan , Eleonora Di Valentino

We investigate dynamical behavior of the equation of state of dark energy $w_{de}$ by employing the linear-spline method in the region of low redshifts from observational data (SnIa, BAO, CMB and 12 $H(z)$ data). The redshift is binned and…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Rong-Gen Cai , Qiping Su , Hong-Bo Zhang