Related papers: Dynamical dark energy with AdS-dS transitions vs. …
Recent baryon acoustic oscillation (BAO) measurements released by DESI, when combined with cosmic microwave background (CMB) data and type Ia supernova (SN) data, suggest a significant preference for dynamical dark energy (DDE) that…
Investigations on dark energy (DE) are currently inconclusive about its time evolution. Hints of this possibility do however glow now and then in the horizon. Herein we assess the current status of dynamical dark energy (DDE) in the light…
We derive multiple constraints on dark energy and compare dynamical dark energy models with a time-varying equation of state ($w_0 w_a$CDM) versus a cosmological constant model ($\Lambda$CDM). We use Baryon Acoustic Oscillation (BAO) from…
The Baryon Acoustic Oscillations (BAO) provide a standard ruler for studying cosmic expansion. The recent observations of BAO in SDSS DR9 and DR11 take measurements of $H(z)$ at several different redshifts. It is argued that the behavior of…
Recent measurements of Baryon Acoustic Oscillations (BAO) from the Dark Energy Spectroscopic Survey (DESI DR2), combined with data from the cosmic microwave background (CMB) and Type Ia supernovae (SNe), challenge the $\Lambda$-Cold Dark…
We investigate a phenomenological extension of the standard $\Lambda$CDM framework, the $\Omega_1\Omega_2$-$\Lambda$CDM model, in which the total energy density of the universe is expanded in powers of $1+z$. This parameterization recovers…
The $\Lambda$CDM model has long served as the cornerstone of modern cosmology, offering an elegant and successful framework for interpreting a wide range of cosmological observations. However, the rise of high-precision datasets has…
Recent results from Type Ia supernovae (SNe Ia) and baryon acoustic oscillations (BAO), in combination with cosmic microwave background (CMB) measurements, have focused renewed attention on dark energy models with a time-varying…
A flat Friedman-Roberson-Walker universe dominated by a cosmological constant ($\Lambda$) and cold dark matter (CDM) has been the working model preferred by cosmologists since the discovery of cosmic acceleration. However, tensions of…
The measurements of baryon acoustic oscillation by the Dark Energy Spectroscopic Instrument Data Release 2 indicate that dark energy may be dynamical with a time-varying equation of state. This has challenged the core assumptions of the…
Joint analysis of the baryon acoustic oscillations (BAO) measurement by the Dark Energy Spectroscopic Instrument (DESI) first data release, Type Ia supernovae (SNe) of the Dark Energy Survey Year 5 (DES5YR) release and cosmic microwave…
We determine constraints on spatially-flat tilted dynamical dark energy XCDM and $\phi$CDM inflation models by analyzing Planck 2015 cosmic microwave background (CMB) anisotropy data and baryon acoustic oscillation (BAO) distance…
Baryon acoustic oscillation measurements by the Dark Energy Spectroscopic Instrument (Data Release 1) have revealed exciting results that show evidence for dynamical dark energy at $\sim3\sigma$ when combined with cosmic microwave…
We present a comprehensive analysis of the cosmological implications of the Dark Energy Spectroscopic Instrument (DESI) Data Release 2 (DR2) Lyman-$\alpha$ forest baryon acoustic oscillation (BAO) measurements, combined with DESI DR2 galaxy…
Baryon Acoustic Oscillation (BAO) provides a powerful tool to measure cosmic expansion and consequently the nature of the Dark Energy (DE). Recent precise BAO measurements by Dark Energy Spectroscopic Instrument data release 1 (DESI DR1),…
The well-known brane world model of cosmology is an alternative to the standard model of cosmology, called {\Lambda}CDM (Lambda Cold Dark Matter) model. However, the quadratical energy density of the brane universe requires an undesirable…
In this article we compare a variety of well known dynamical dark energy models using the cosmic microwave background measurements from the 2018 Planck legacy and 2015 Planck data releases, the baryon acoustic oscillations measurements and…
We investigate the dynamics and cosmological implications of dark energy (DE), modeled as a scalar field with a hyperbolic tangent potential that induces a smooth shift in the effective cosmological constant (CC), encompassing transitions…
We present strong evidence for dynamical dark energy that challenges the standard $\Lambda$CDM model. Several dark energy scenarios are explored, including $\omega_0\omega_a$CDM, logarithmic, exponential, JBP, and BA parameterizations,…
We present a Bayesian comparative analysis of five cosmological models: $\Lambda$CDM, $w$CDM, $w_0w_a$CDM, $\phi$CDM (with scalar-field dark energy), and an interacting dark energy scenario (the $\xi$-index model), to investigate dark…