Related papers: Constraints to dark energy using PADE parameterisa…
The latest findings from the DESI (Dark Energy Spectroscopic Instrument) data release 1 (DR1) [1], combined with data from the cosmic microwave background and supernovae, suggest a preference for dynamical dark energy over the cosmological…
In this paper, we assemble a catalog of 118 strong gravitational lensing systems from SLACS, BELLS, LSD and SL2S surveys and use them to constrain the cosmic equation of state. In particular we consider two cases of dark energy…
A comparative study of various parametrizations of the dark energy equation of state $w(z)$ and its variation with the redshift is made. Astrophysical constraints from 'integrated tracking' are laid down to test the physical viability and…
Recent cosmological measurements are hinting that dark energy may evolve, with its equation of state, $w_\mathrm{DE}$, even showing oscillatory patterns. In this work, we employ a model-independent approach to jointly reconstruct…
A $\Lambda$CDM model with dark matter that decays into inert relativistic energy on a timescale longer than the Hubble time will produce an expansion history that can be misinterpreted as stable dark matter with time-varying dark energy. We…
We consider an Early Dark Energy (EDE) cosmological model, and perform an analysis which takes into account both background and perturbation effects via the parameters $c^{2}_{\rm eff}$ and $c^{2}_{\rm vis}$, representing effective sound…
We use measurements from the Planck satellite mission and galaxy redshift surveys over the last decade to test three of the basic assumptions of the standard model of cosmology, $\Lambda$CDM: the spatial curvature of the universe, the…
We use the non-linear spherical model in cold dark matter (CDM) cosmologies with dark energy to investigate the effects of dark energy on the growth of structure and the formation of virialised structures. We consider dark energy models…
The DESI collaboration have recently analyzed their first year of data, finding a preference for thawing dark energy scenarios when using parameterized equations of state for dark energy. We investigate whether this preference persists when…
We present a Dark Energy (DE) model with a sound derivation as a natural extension of the Standard Model of particle physics with no free parameters and an excellent fit with current cosmological data improving by 21% the $\Lambda$CDM fit…
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,…
Chevallier-Polarski-Linder (CPL) parametrization for the equation of state of dark energy in terms of cosmic redshift or scale factor have been frequently studied in the literature. In this study, we consider cosmic time based CPL…
Dark Energy not only has background effects through its equation of state $w_{DE}$, but also it can cluster through its sound speed $c^2_{sDE}$, subject to certain conditions. As is well-known, for dynamical dark energy models, dark energy…
We compute the number density of massive Black Holes (BHs) at the centre of galaxies at z=6 in different Dynamical Dark Energy (DDE) cosmologies, and compare it with existing observational lower limits, to derive constraints on the…
Confirmation of accelerated expansion of the universe probed the concept of dark energy theory, and since then, numerous models have been introduced to explain its origin and nature. The present work is based on reconstructing dark energy…
We baseline with current cosmological observations to forecast the power of the Dark Energy Spectroscopic Instrument (DESI) in two ways: 1. the gain in constraining power of parameter combinations in the standard $\Lambda$CDM model, and 2.…
In the present investigation we use observational data of $ f \sigma_ {8} $ to determine observational constraints in the plane $(\Omega_{m0},\sigma_{8})$ using two different methods: the growth factor parametrization and the numerical…
In this paper, the properties of dark energy are investigated according to the parameterized deceleration parameter $q(z)$, which is used to describe the extent of the accelerating expansion of the universe. The potential of dark energy…
We study the performance of the flat $\Lambda$CDM model and the dynamical dark energy parameterizations $w_0$CDM and $w_0w_a$CDM, in which the dark energy (DE) equation of state is either constant ($w=w_0$) or redshift-dependent…
Recently, the measurements of baryon acoustic oscillations (BAO) by the Dark Energy Spectroscopic Instrument (DESI) indicate a potential deviation from the standard $\Lambda$CDM model. Some studies suggest that the data points from the…