Related papers: Nonparametric determination of redshift evolution …
A huge amount of good quality astrophysical data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision…
Understanding the acceleration of the universe and its cause is one of the key problems in physics and cosmology today, and is best studied using a variety of mutually complementary approaches. Daly and Djorgovski (2003, 2004) proposed a…
This paper explores the dark energy phenomenon within the context of $f(R,L_m)$ gravity theory. Two specific non-linear $f (R, L_m)$ models are considered: $f(R,L_m)=\frac{R}{2}+L_m^\alpha$ and $f(R,L_m)=\frac{R}{2}+(1+\alpha R)L_m$, where…
The primary purpose of this work is the provision of accurate, analytic, evolutionary templates for cosmological parameters and fundamental constants in a dynamical cosmology. A flat quintessence cosmology with a dark energy potential that…
Here we test different models of dark energy beyond the standard cosmological constant scenario. We start considering the CPL parameterization of the equation of state (EOS), then we consider a dark energy scalar field (Quintessense).…
We look for evidence for the evolution in dark energy density by employing Principal Component Analysis (PCA). Distance redshift data from supernovae and baryon acoustic oscillations (BAO) along with WMAP7 distance priors are used to put…
In this paper, we study a model which is composed by the cosmological constant and dark matter with nonzero equation of state parameter, which could be called as $\Lambda$wDM. In the synchronous gauge, we obtain the perturbation equations…
We propose a model-independent parametrization of dark energy motivated by thermodynamics. To this aim, we consider Pad\'e polynomials to reconstruct the form of deceleration parameter adequate to describe different epochs of cosmic history…
The redshift of all cosmological sources drifts by a systematic velocity of order a few m/s over a century due to the deceleration of the Universe. The specific functional dependence of the predicted velocity shift on the source redshift…
Photometric redshift estimation is an indispensable tool of precision cosmology. One problem that plagues the use of this tool in the era of large-scale sky surveys is that the bright galaxies that are selected for spectroscopic observation…
Understanding the physical nature of the dark energy which appears to drive the accelerated expansion of the unvierse is one of the key problems in physics and cosmology today. This important problem is best studied using a variety of…
We study the imprint of non-standard dark energy (DE) and dark matter (DM) models on the 21cm intensity map power spectra from high-redshift neutral hydrogen (HI) gas. To this purpose we use halo catalogs from N-body simulations of…
Evolution of the universe with modified holographic Ricci dark energy model is considered. Dependency of the equation of state parameter and deceleration parameter on the redshift and model parameters are obtained. It is shown that the…
We study the nonlinear growth of cosmic structure in different dark energy models, using large volume N-body simulations. We consider a range of quintessence models which feature both rapidly and slowly varying dark energy equations of…
We compute the Bayesian evidences for one- and two-parameter models of evolving dark energy, and compare them to the evidence for a cosmological constant, using current data from Type Ia supernova, baryon acoustic oscillations, and the…
Dynamical dark energy has gained renewed interest due to recent theoretical and observational developments. In the present paper, we focus on a string-motivated dark energy set-up, and perform a detailed cosmological analysis of exponential…
We study the evidence for dark energy (DE) evolution at low redshift, using baryonic acoustic oscillations (BAOs) from the DESI Early Data Release, Pantheon+ Type Ia supernovae (SNe-Ia), and redshift space distortions (RSDs) to constrain…
A data-driven approach to elucidating the nature of the dark energy, in the form of a joint analysis of a full set of cosmological parameters, utilizing all available observational data is proposed. A parameterization of a generalized dark…
Recently, a model of modified gravity plus single scalar field model was proposed, in which the scalar couples both to the standard Riemannian volume form given by the square root of the determinant of the Riemannian metric, as well as to…
While $f(T)$ gravity has shown considerable potential in addressing cosmological tensions, we explore previously overlooked solution spaces that hold further promise. We examine the case where the customary assumption of a strictly positive…