Related papers: $S_8$ increases with effective redshift in $\Lambd…
A new kind of accelerating flat model with no dark energy that is fully dominated by cold dark matter (CDM) is investigated. The number of CDM particles is not conserved and the present accelerating stage is a consequence of the negative…
We place observational constraints on two models within a class of scenarios featuring an elastic interaction between dark energy and dark matter that only produces momentum exchange up to first order in cosmological perturbations. The…
In a model of the late-time cosmic acceleration within the framework of generalized Proca theories, there exists a de Sitter attractor preceded by the dark energy equation of state $w_{\rm DE}=-1-s$, where $s$ is a positive constant. We run…
We present a measurement of the amplitude of matter fluctuations over the redshift range 0.8 <= z <= 3.5 from the cross correlation of over 1.2 million spectroscopic quasars selected by the Dark Energy Spectroscopic Instrument (DESI) across…
We present a cosmographic study designed to test the simplest type of accelerating cosmology: a flat universe with matter and a cosmological constant ($\Lambda$). Hubble series expansions are fit to the SCP Union2.1 supernova data set to…
We present a joint analysis of the Planck cosmic microwave background (CMB) and Baryon Oscillation Spectroscopic Survey (BOSS) final data releases. A key novelty of our study is the use of a new full-shape (FS) likelihood for the…
Planck data provide precise constraints on cosmological parameters when assuming the base $\Lambda$CDM model, including a $0.17\%$ measurement of the age of the Universe, $t_0=13.797 \pm 0.023\,{\rm Gyr}$. However, the persistence of the…
The current expansion rate of the Universe, the Hubble constant $H_0$, is an important cosmological quantity. However, two different ways to measure its value do not agree -- building a low-redshift distance ladder leads to a higher value…
The Hubble tension persists as a challenge in cosmology. Even early dark energy (EDE) models, initially considered the most promising for alleviating the Hubble tension, fall short of addressing the issue without exacerbating other…
We present relativistic $N$-body simulations of a $\Lambda_{\rm s}$CDM - sign-switching cosmological constant (CC) - scenario under general relativity and compare its nonlinear matter power spectrum to $\Lambda$CDM at ${z =…
The concept of a rapidly sign-switching cosmological constant, interpreted as a mirror AdS-dS transition in the late universe and known as the $\Lambda_{\rm s}$CDM, has significantly improved the fit to observational data, offering a…
Under the assumption of a flat Lambda-CDM cosmology, recent data from the Planck satellite point toward a Hubble constant that is in tension with that measured by gravitational lens time delays and by the local distance ladder. Prosaically,…
We examine the performance of the six-parameter $\Lambda$CDM model and its extensions in light of recent cosmological observations, with particular focus on neutrino properties inferred from cosmology. Using a broad suite of nine…
We investigate the Hubble tension in the non-flat Super-$\Lambda {\rm CDM}$ model. The non-flat Super-$\Lambda {\rm CDM}$ model extends the Super-$\Lambda {\rm CDM}$ model by including the spatial curvature as a free parameter. The…
In the last years with the increasing precision in cosmological observations we have been able to establish a standard model of cosmology, the so-called $\Lambda$CDM, but also find some tensions between cosmological probes that are…
The discrepancy between the value of the Hubble constant $H_0$ in the late, local universe and the one obtained from the Planck collaboration representing an all-sky value for the early universe reached the 5-$\sigma$ level. Approaches to…
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…
The $\Lambda$ Cold Dark Matter model ($\Lambda$CDM) represents the current standard model in cosmology. Within this, there is a tension between the value of the Hubble constant, $H_0$, inferred from local distance indicators and the angular…
We present constraints on extensions to the $\Lambda$CDM cosmological model from measurements of the $E$-mode polarization auto-power spectrum and the temperature-$E$-mode cross-power spectrum of the cosmic microwave background (CMB) made…
The mismatch between different independent measurements of the expansion rate of the Universe is known as the Hubble constant ($H_0$) tension, and it is a serious and pressing problem in cosmology. We investigate this tension considering…