Related papers: Parameterizing and Measuring Dark Energy Trajector…
We constrain the evolution of dark matter energy density over time, specifically focusing on deviation from the standard model represented by the equation $\rho_{m}\propto(1+z)^{3-\varepsilon}$, where $\varepsilon$ is a constant parameter.…
We use the recent type Ia supernova, cosmic microwave background and large-scale structure data to shed light on the temporal evolution of the dark energy equation of state $w(z)$ out to redshift one. We constrain the most flexible…
In this paper, a well-motivated parametrization of the Hubble parameter ($H$% ) is revisited that renders two models of dark energy showing some intriguing features of the late-time accelerating Universe. A general quintessence field is…
We study the late-time cosmological dynamics of a two-field dark energy model consisting of a canonical quintessence scalar field and a phantom scalar field in a spatially flat FLRW universe. The fields are minimally coupled to gravity and…
We report on constraints to the cosmological jerk parameter ($j$) and to possible variability of the fine-structure constant ($\Delta \alpha/\alpha$) based on stochastic quintessence models of dark energy, discussed by Chongchitnan and…
We show that the abundance and redshift distribution ($dN/dz$) of galaxy clusters in future high--yield cluster surveys, combined with the spatial power spectrum ($P_c(k)$) of the same clusters, can place significant constraints on 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…
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…
Future galaxy redshift surveys aim to measure cosmological quantities from the galaxy power spectrum. A prime example is the detection of baryonic acoustic oscillations (BAOs), providing a standard ruler to measure the dark energy equation…
The first and second year results of DESI provide consistent evidence that dark energy may not be quantum vacuum energy ($\Lambda$). If true, this would be an extraordinary development in the 25-year quest to understand cosmic acceleration.…
We consider how well the dark energy equation of state $w$ as a function of red shift $z$ will be measured using current and anticipated experiments. We use a procedure which takes fair account of the uncertainties in the functional…
A model-independent method to study the possible evolution of dark energy is presented. Optimal estimates of the dark energy equation of state w are obtained from current supernovae data from Riess et al. (2004) following a principal…
The quest for understanding the late-time acceleration is haunted by an immense freedom in the analysis of dynamical models for dark energy in extended parameter spaces. Often-times having no prior knowledge at our disposal, arbitrary…
We introduce a set of two-parameter models for the dark energy equation of state (EOS) $w(z)$ to investigate time-varying dark energy. The models are classified into two types according to their boundary behaviors at the redshift…
We study the constraints which the next generation of radio telescopes could place on the nature of dark energy, dark matter and inflation by studying the gravitational lensing of high redshift 21 cm emission, and we compare with the…
The explanation of the accelerated expansion of the Universe poses one of the most fundamental questions in physics and cosmology today. If the acceleration is driven by some form of dark energy, one can try to constrain the parameters…
Accurate measurements of fundamental cosmological parameters, especially the Hubble constant (H_0) and present-day matter density (\Omega_{m0}), are crucial for constraining dark energy (DE) evolution. We analyze the sensitivities of…
Dark energy is a premier mystery of physics, both theoretical and experimental. As we look to develop plans for high energy physics over the next decade, within a two decade view, we consider benchmarks for revealing the nature of dark…
This article discusses a dark energy cosmological model in the standard theory of gravity - general relativity with a broad scalar field as a source. Exact solutions of Einstein's field equations are derived by considering a particular form…
In this work, FRW universe filled with dark matter (perfect fluid with negligible pressure) along with dark energy in the background of Galileon gravity is considered. Four dark energy models with different EoS parametrizations have been…