相关论文: Constraints on dark energy and quintessence with a…
Detections of local maxima in the density perturbation spectrum at characteristic comoving scales L~100-200h^{-1}Mpc have previously been claimed. Here, this cosmic standard ruler is sought in the ``10K'' release of the 2dF QSO Redshift…
Where's the matter? The answer seems to be: ``distributed according to a power spectrum with at least one feature (local maximum) near 120-130h^-1Mpc''. Analyses of the Iovino, Clowes & Shaver quasar candidate catalogue at z~2 and the 2dF…
Several observational analyses suggest that matter is spatially structured at $\approx 130h^{-1}Mpc$ at low redshifts. This peak in the power spectrum provides a standard ruler in comoving space which can be used to compare the local…
We search for the most suitable set of cosmological parameters that describes the observable universe. The search includes the possibility of quintessential flat universes, i.e., the analysis is restricted to the determination of the…
The large-scale maximum at k~0.05 identified in the power-spectrum of galaxy fluctuations provides a co-moving scale for measuring cosmological curvature. In shallow 3D surveys the peak is broad, but appears to be well resolved in 1D, at…
We use the number density of peaks in the smoothed cosmological density field taken from the 2dF Galaxy Redshift Survey to constrain parameters related to the power spectrum of mass fluctuations, n (the spectral index), dn/d(lnk) (rolling…
We revisit the power spectrum analysis of the complete sample of the two degree field (2dF) QSO redshift (2QZ) survey, as a complementary test of the work by Outram et al. (2003). A power spectrum consistent with that of the 2QZ group is…
We report on measurements of the cosmological constant, Lambda, and the redshift space distortion parameter beta=Omega_m^0.6/b, based on an analysis of the QSO power spectrum parallel and perpendicular to the observer's line of sight, from…
Exclusion zones in the cross-correlations between critical points (peak-void, peak-wall, filament-wall, filament-void) of the density field define quasi-standard rulers that can be used to constrain dark matter and dark energy cosmological…
We have run Monte Carlo simulations, for quasar clustering redshift distortions in the Two-Degree Field QSO Redshift Survey (2QZ), in order to elicit the power of redshift distortions (geometric Alcock-Paczynski and linear kinematic) to…
Cosmological theories for the origin and evolution of structure in the Universe are highly predictive of the form of the angular power spectrum of cosmic microwave background fluctuations. We present new results from a comprehensive study…
In the almost Friedmann-Lema^itre model of the Universe, the density parameter, Omega_matter, and the cosmological constant, Omega_Lambda, measure curvature. Several linearly degenerate relations between these two parameters have recently…
In this paper we obtain constraints on the cosmological density parameters, \Omega_m and \Omega_b, by comparing the preliminary measurement of the QSO power spectrum from the two degree field QSO redshift survey with results from an…
A comparison between the line of sight power spectrum of absorption in the Lyman-alpha forest and the cross power spectrum between the absorption in neighboring lines of sight offers an evolution-free means to constrain the cosmological…
We constrain flat cosmological models with a joint likelihood analysis of a new compilation of data from the cosmic microwave background (CMB) and from the 2dF Galaxy Redshift Survey (2dFGRS). Fitting the CMB alone yields a known degeneracy…
We combine complementary datasets to constrain dark energy. Using standard Big Bang Nucleosynthesis and the observed abundances of primordial nuclides to put constraints on $\Omega_Q$ at temperatures near $T \sim 1MeV$, we find the strong…
We derive constraints on cosmological parameters using the power spectrum of galaxy clustering measured from the final two-degree field galaxy redshift survey (2dFGRS) and a compilation of measurements of the temperature power spectrum and…
We use some of the recently released observational data to test the viability of two classes of minimally coupled scalar field models of quintessence with exponential potentials for which exact solutions of the Einstein equations are known.…
Fluctuations in the CMB have now been detected over a wide range of angular scales, and a consistent picture seems to be emerging. The data cannot currently constrain a large number of cosmological parameters, but it is clear that there is…
The 2dF Galaxy Redshift Survey is the first to observe more than 100,000 redshifts. This allows precise measurements of many of the key statistics of galaxy clustering, in particular redshift-space distortions and the large-scale power…