Related papers: A cosmological test with compact radio sources
In view of new experimental results that strongly suggest a non-zero cosmological constant, it becomes interesting to revisit the Friedman-Lemaitre model of evolution of a universe with cosmological constant and radiation pressure. In this…
Volonteri et al. (2011) found that the number of radio-loud quasars above redshift 4 calculated from the luminosity function (based upon Swift/BAT observations) is much smaller than the number estimated from the known high-redshift beamed…
Nodland and Ralston (astro-ph/9704196) claim evidence for a wavelength-independent cosmic birefringence. Although it has been shown (astro-ph/9704247, astro-ph/9704263) that the data analysed did not support this conclusion, the possibility…
Distance duality relation (DDR) marks a fundamental difference between expanding and nonexpanding Universes, as an expanding metric causes angular diameter distance smaller than luminosity distance by an extra factor of $(1+z)$. Here we…
For known gravitational lens systems the redshift distribution of the lenses is compared with theoretical expectations for $10^{4}$~Friedmann-Lema\^\i tre~cosmological models, which more than cover the range of possible cases. The…
We use cosmography to present constraints on the kinematics of the Universe without postulating any underlying theoretical model a priori. To this end, we use a Markov Chain Monte Carlo analysis to perform comparisons to the supernova Ia…
With the many ambitious proposals afoot for new generations of very large telescopes, along with spectrographs of unprecedented resolution, there arises the real possibility that the time evolution of the cosmological redshift may, in the…
We investigate the capability of Einstein Telescope to constrain the cosmological parameters of the non-flat $\Lambda$CDM cosmological model. Two types of mock datasets are considered depending on whether or not a short Gamma-Ray Burst is…
We review observational tests for the homogeneity of the Universe on large scales. Redshift and peculiar velocity surveys, radio sources, the X-Ray Background, the Lyman-$\alpha$ forest and the Cosmic Microwave Background are used to set…
Cosmological distances are fundamental observables in cosmology. The luminosity ($D_L$), angular diameter ($D_A$) and gravitational wave ($D_{\rm GW}$) distances are all trivially related in General Relativity assuming no significant…
We use angular size versus redshift data for galaxy clusters from Bonamente et al. (2006) to place constraints on model parameters of constant and time-evolving dark energy cosmological models. These constraints are compatible with those…
General relativity reproduces main current cosmological observations, assuming the validity of cosmic distance duality relation (CDDR) at all scales and epochs. However, CDDR is poorly tested in the redshift interval between the farthest…
Simple cosmological models based upon five-dimensional Kaluza-Klein relativity are re-examined and interesting properties are indicated. These models are special cases of those obtained by Davidson et al. and Mann and Vincent, specifically,…
The Sunyaev-Zel'dovich (SZ) effect from clusters of galaxies should yield a significant signal in cosmic microwave background(CMB) experiments at small angular scales ($\ell \ga 1000$). Experiments with sufficient frequency coverage should…
We propose a simple method for determining the redshift $z_{m}$ at which the angular size of an extragalactic source with fixed proper diameter takes its minimal value. A closed analytical expression, which is quite convenient for numerical…
A measurement of the redshift drift constitutes a model-independent probe of fundamental cosmology. Several approaches are being considered to make the necessary observations, using (i) the Extremely Large Telescope (ELT), (ii) the Cosmic…
We review cosmological inference from galaxy surveys at low and high redshifts, with emphasis on new Southern sky surveys. We focus on several issues: (i) The importance of understanding selection effects in catalogues and matching Northern…
We combine the LOw-Frequency ARray (LOFAR) Two-metre Sky Survey (LoTSS) second data release (DR2) catalogue with gravitational lensing maps from the Cosmic Microwave Background (CMB) to place constraints on the bias evolution of LoTSS radio…
We examine the possibility of constraining the cosmological mean mass and dark energy densities by an application of the Alcock-Paczynski test on redshifted 21-cm maps of the epoch of reionization. The 21-cm data will be provided as a…
In this paper, by using the recently compiled set of 120 intermediate-luminosity quasars (ILQSO) observed in a single-frequency VLBI survey, we propose an improved model-independent method to probe cosmic curvature parameter $\Omega_k$ and…