相关论文: Uncorrelated Estimates of Dark Energy Evolution

One of the key issues in cosmology is to establish the nature of dark energy, and to determine whether the equation of state evolves with time. When estimating this from distance measurements there is a degeneracy with the matter density.…

In this paper, we use the type Ia supernovae data to constrain the holographic dark energy model proposed by Li. We also apply a cosmic age test to this analysis. We consider in this paper a spatially flat Friedmann-Robertson-Walker…

We discuss the possibility to identify anisotropic and/or inhomogeneous cosmological models using type Ia supernova data. A search for correlations in current type Ia peak magnitudes over a large range of angular scales yields a null…

We discuss the possible consistency of the recently discovered Type Ia supernovae at z>1 with models in which dark energy is strongly coupled to a significant fraction of dark matter, and in which an (asymptotic) accelerated phase exists…

In the Cardassian model, dark energy density arises from modifications to the Friedmann equation, which becomes $H^2 = g(\rhom)$, where $g(\rhom)$ is a new function of the energy density. The universe is flat, matter dominated, and…

The discovery of dark energy by the first generation of high-redshift supernova surveys has generated enormous interest beyond cosmology and has dramatic implications for fundamental physics. Distance measurements using supernova explosions…

A new component of the Universe which leads to an accelerated cosmic expansion is found from the measurements of distances to high-redshift type Ia supernovae. We describe the method and the results obtained from the observations of distant…

We investigate observational constraints on the curvature of the universe not restricting ourselves to a cosmological constant as dark energy, in particular allowing a dark energy equation of state to evolve with time in several ways. We…

We review the ability of redshift surveys to provide constraints on the Dark Energy content of the Universe. The matter power spectrum and dynamics at the present epoch are nearly `blind' to Dark Energy, but combined with the CMB they can…

We examine how dark energy constraints from current observational data depend on the analysis methods used: the analysis of Type Ia supernovae (SNe Ia), and that of galaxy clustering data. We generalize the flux-averaging analysis method of…

In this paper, we use the joint measurement of geometry and growth rate from matter density perturbations to constrain the holographic dark energy model. The geometry measurement includes type Ia supernovae (SN Ia) Union2.1, full…

The most detailed constraints on the accelerating expansion of the universe and details of nature of dark energy are derived from the high redshift supernova data, assuming that the errors in the measurements are Gaussian in nature. There…

We discuss bounds on the cosmological relativistic energy density as a function of redshift, reviewing the big bang nucleosynthesis and cosmic microwave background bounds, updating bounds from large scale structure, and introducing a new…

We investigate a class of dark energy models in which the equation of state undergoes a rapid transition and for which the Hubble SN Ia diagram is known to be poorly discriminant. Interestingly enough, we find that transitions at high…

In this work, we have proposed a general dark energy density parametrization to study the evolution of the universe. We have also constrained the model parameters using the combination of Type Ia supernova (SNIa), baryonic acoustic…

We perform a cosmological parameter analysis of the 75 square degree CTIO lensing survey in conjunction with CMB and Type Ia supernovae data. For Lambda CDM cosmologies, we find that the amplitude of the power spectrum at low redshift is…

Recent measurements of type Ia supernovae as well as other concordant observations suggest that the expansion of our universe is accelerating. A dark energy component has usually been invoked as the most feasible mechanism for the…

Relatively uniform light curves and spectral evolution of Type Ia supernovae (SNe Ia) have led to the use of SNe Ia as a ``standard candle'' to determine cosmological parameters, such as the Hubble constant, the density parameter, and the…

The recent robust and homogeneous analysis of the world's supernova distance-redshift data, together with cosmic microwave background and baryon acoustic oscillation data, provides a powerful tool for constraining cosmological models. Here…

Reconstructing the evolution history of the dark energy equation of state parameter $w(z)$ directly from observational data is highly valuable in cosmology, since it contains substantial clues in understanding the nature of the accelerated…