Related papers: Einstein-Cartan cosmology and the S8 problem
We use recently published redshift space distortion measurements of the cosmological growth rate, f sigma_8(z), to examine whether the linear evolution of perturbations in the R_h=ct cosmology is consistent with the observed development of…
Hubble constant $H_0$ and weighted amplitude of matter fluctuations $S_8$ determinations are biased to higher and lower values, respectively, in the late Universe with respect to early Universe values inferred by the Planck collaboration…
Measurements of weak gravitational lensing at low redshifts ($z\lesssim 0.5-1$), quantified by the parameter $S_8$, favor weaker matter clustering than that expected from the standard $\Lambda$CDM cosmological model with parameters…
The current discrepancy between the CMB and weak lensing measurements of the amplitude of matter fluctuations, the so-called $S_8$ tension, has attracted a great deal of recent attention, as it may show a crack in the $\Lambda$CDM model of…
We present constraints on the amplitude of matter fluctuations from the clustering of galaxies and their cross-correlation with the gravitational lensing convergence of the cosmic microwave background (CMB), focusing on low redshifts…
Within the $\Lambda$CDM model, measurements from recent Cosmic Microwave Background (CMB) and weak lensing (WL) surveys have uncovered a $\sim 3\sigma$ disagreement in the inferred value of the parameter $S_8 \equiv…
This study is devoted to the implications of scale-dependent gravity in Cosmology. Redshift-space distortion data indicate that there is a tension between $\Lambda$CDM and available observations as far as the value of the rms density…
One problem of the $\Lambda$CDM model is the tension between the $S_8$ found in Cosmic Microwave Background (CMB) experiments and the smaller one obtained from large-scale observations in the late Universe. The $\sigma_8$ quantifies the…
The amplitude of cosmological density fluctuations, sigma_8, has been studied and estimated by analysing many cosmological observations. The values of the estimates vary considerably between the various probes. However, different estimators…
The excellent measurements of the cosmic microwave background (CMB) fluctuations by Planck allow us to tightly constrain the amplitude of matter fluctuations at redshift $\sim 1100$ in the $\Lambda$-cold dark matter ($\Lambda$CDM) model.…
We consider constraints on the amplitude of mass fluctuations in the universe, sigma_8, derived from two simple observations: the present number density of clusters and the amplitude of their correlation function. Allowing for the…
The $S_8$ tension between low-redshift galaxy surveys and the primary CMB signals a possible breakdown of the $\Lambda$CDM model. Recently differing results have been obtained using low-redshift galaxy surveys and the higher redshifts…
Weak galaxy lensing surveys have consistently reported a lower amplitude for the matter fluctuation spectrum, as measured by the $S_8$ parameter, than expected in the $\Lambda{\rm CDM}$ cosmology favoured by $Planck$. However, the expansion…
[Abridged] We use data on massive galaxy clusters ($M_{\rm cluster} > 8 \times 10^{14} h^{-1} M_\odot$ within a comoving radius of $R_{\rm cluster} = 1.5 h^{-1}\Mpc$) in the redshift range $0.05 \lesssim z \lesssim 0.83$ to place…
We present a novel simulation-based cosmological analysis of galaxy-galaxy lensing and galaxy redshift-space clustering. Compared to analysis methods based on perturbation theory, our simulation-based approach allows us to probe a much…
We use the observed abundance and clustering of galaxies from the 2dFGRS to determine the matter density Omega_m and the linear amplitude of mass fluctuations sigma_8. We use a method based on the conditional luminosity function, which…
A number of recent, low-redshift, lensing measurements hint at a universe in which the amplitude of lensing is lower than that predicted from the $\Lambda$CDM model fit to the data of the Planck CMB mission. Here we use the auto- and…
Fluctuations in sky maps of the galaxy redshifts, dubbed as angular redshift fluctuations (ARF), contain precise information about the growth rate of structures and the nature of gravity in the Universe. Specifically, ARF constrain the…
We describe a tomographic dissection of the Planck CMB lensing data, cross-correlating this map with galaxies in different ranges of photometric redshift. We use the nearly all-sky 2MPZ and WISExSCOS catalogues for z<0.35, extending to…
We explore the effects of incorporating redshift uncertainty into measurements of galaxy clustering and cross-correlations of galaxy positions and cosmic microwave background (CMB) lensing maps. We use a simple Gaussian model for a redshift…