相关论文: Constraining Perturbative Early Dark Energy with C…
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…
Observational constraints are considered on a $w_{log}$CDM model of the dark energy equation of state, $w_{d}(z) = w_{0} + w_{a}\left( \frac{\ln(2+z)}{1+z} - \ln 2 \right)$, using the most recent cosmological datasets including DESI Baryon…
The recent cosmological picture contains a significant tension indicating that our standard $\Lambda$CDM picture may be incomplete. Early Dark Energy models can alleviate the Hubble tension, by assuming an early acceleration that could…
Motivated by the current status of the cosmological observations and significant tensions in the estimated values of some key parameters assuming the standard $\Lambda$CDM model, we propose a simple but radical phenomenological emergent…
Numerous upcoming observations, such as WFIRST, BOSS, BigBOSS, LSST, Euclid, and Planck, will constrain dark energy (DE)'s equation of state with great precision. They may well find the ratio of pressure to energy density, $w$, is -1,…
We consider the linear growth of matter perturbations in various dark energy (DE) models. We show the existence of a constraint valid at $z=0$ between the background and dark energy parameters and the matter perturbations growth parameters.…
Cosmological models with variable and modified equations of state for dark energy are confronted with observational data, including Type Ia supernovae, Hubble parameter data $H(z)$ from different sources, and observational manifestations of…
Current cosmological data exhibit discordance between indirect and some direct inferences of the present-day expansion rate, $H_0$. Early dark energy (EDE), which briefly increases the cosmic expansion rate prior to recombination, is a…
We use late Universe probes - Type Ia Supernovae from the PantheonPlus compilation, Quasars, and Dark Energy Spectroscopic Instrument (DESI) Data Release 1 (DR1) BAO data - along with Cosmic Chronometers or Megamasers to constrain various…
We propose a novel parameterization of the dark energy density. It is particularly well suited to describe a non-negligible contribution of dark energy at early times and contains only three parameters, which are all physically meaningful:…
A promising idea to resolve the long standing Hubble tension is to postulate a new subdominant dark-energy-like component in the pre-recombination Universe which is traditionally termed as the Early Dark Energy (EDE). However, as shown in…
In this paper, we consider a recently proposed model of Dark Energy (DE) know as Modified Holographic Ricci DE (MHRDE) (which is function of the Hubble parameter and its first derivative with respect to the cosmic time $t$) in the light of…
Constraining simultaneously the Dark Energy(DE) equation of state and the curvature of the Universe is difficult due to strong degeneracies. To circumvent this problem when analyzing data it is usual to assume flatness to constrain DE, or…
The tension between the Hubble constant ($H_0$) inferred from the cosmic microwave background (CMB) and that measured from late-time observations, such as the local distance ladder, is a major challenge in modern cosmology. Early dark…
We reconstruct evolution of the dark energy (DE) density using a nonparametric Bayesian approach from a combination of latest observational data. We caution against parameterizing DE in terms of its equation of state as it can be singular…
We present updated observational constraints on the spatially flat $\phi$CDM model, where dark energy is described by a minimally coupled scalar field $\phi$ with an inverse power-law potential $V=V_0 \phi^{-\alpha}$. Using Planck 2018 CMB…
We investigate future constraints on early dark energy (EDE) achievable by the Planck and CMBPol experiments, including cosmic microwave background (CMB) lensing. For the dark energy, we include the possibility of clustering through a sound…
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…
We construct a new model of quintessential $\alpha$ attractor inflation in conjunction with the features of non-oscillating early dark energy (EDE). Slow-roll plateau of this model is obtained, and analyzed in $k$-space, through the…
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…