Related papers: Testing the local supervoid solution to the Hubble…
We revisit the constraints on inflation models by using the current cosmological observations involving the latest local measurement of the Hubble constant ($H_{0} = 73.00\pm 1.75$ km s $^{-1}$ Mpc$^{-1}$). We constrain the primordial power…
We use the dispersion measure (DM) and redshift measurements of 24 localized fast radio bursts (FRBs) to compare cosmological models and investigate the Hubble tension. Setting a flat prior on the DM contribution from the Milky Way's halo,…
The Hubble tension refers to the discrepancy in the value of the Hubble constant $H_0$ inferred from the cosmic microwave background observations, assuming the concordance $\Lambda$CDM model of the Universe, and that from the distance…
The Universe expansion rate is modulated around local inhomogeneities due to their gravitational potential. Velocity waves are then observed around galaxy clusters in the Hubble diagram. This paper studies them in a ~738 Mpc wide, with…
Dynamical dark energy has been recently suggested as a promising and physical way to solve the 3.4 sigma tension on the value of the Hubble constant $H_0$ between the direct measurement of Riess et al. (2016) (R16, hereafter) and the…
Recently, observational data and high precision mapping of the local velocity field of Local Group and Virgo cluster have revealed a linear velocity-distance relation of the outermost galaxies, properly referred to as Local Hubble Flow. By…
We evaluate the local variance of the Hubble Constant $H_0$ with low-z Type Ia Supernovae (SNe). Our analyses are performed using a hemispherical comparison method in order to test whether taking the bulk flow motion into account can…
In the standard cosmological model, the dimming of distant Type Ia supernovae is explained by invoking the existence of repulsive `dark energy' which is causing the Hubble expansion to accelerate. However this may be an artifact of…
The mismatch between the locally measured expansion rate of the universe and the one inferred from the cosmic microwave background measurements by Planck in the context of the standard $\Lambda$CDM, known as the Hubble tension, has become…
In the standard (LCDM) model of cosmology the universe has emerged out of an early homogeneous and isotropic phase. Structure formation is associated with the growth of density irregularities and peculiar velocities. Our Local Group is…
The suggestion that we occupy a privileged position near the centre of a large, nonlinear, and nearly spherical void has recently attracted much attention as an alternative to dark energy. Putting aside the philosophical problems with this…
Recently, we constructed the specific solution to the second-order cosmological perturbation theory, around any Friedmann-Lemaitre-Robertson-Walker (FLRW) background filled with dust matter and a positive cosmological constant. In this…
We present an improved Minimal Variance (MV) method for using a radial peculiar velocity sample to estimate the average of the three-dimensional velocity field over a spherical volume, which leads to an easily interpretable bulk flow…
An independent determination of $H_0$ is crucial given the growing tension between the Hubble constant, $H_0$, derived locally and that determined from the modeling of the cosmic microwave background (CMB) originating in the early universe.…
The open problems related to cosmological tensions in current times have opened new paths to study new probes to constrain cosmological parameters in standard and extended cosmologies, in particular, to determine at a local level the value…
There has been considerable interest in recent years in cosmological models in which we inhabit a very large, underdense void as an alternative to dark energy. A longstanding objection to this proposal is that observations limit our…
Observational constraints are considered on a $w_{log}$CDM model of the dark energy equation of state, $w_{d}(z) = w_{0} + w_{a}\left( \frac{\ln(2+z)}{1+z} - \ln 2 \right)$, using the most recent cosmological datasets including DESI Baryon…
Holographic dark energy (HDE) describes the vacuum energy in a cosmic IR region whose total energy saturates the limit of avoiding the collapse into a black hole. HDE predicts that the dark energy equation of the state transiting from…
The Coma cluster, embedded in a cosmic filament, is a complex and dynamically active structure in the local Universe. Applying a density-based member selection dbscan to data from the Sloan Digital Sky Survey (SDSS), we identify cluster…
Recent measurements of the parameters of the Concordance Cosmology Model ($\Lambda$CDM) done in the low-redshift Universe with Supernovae Ia/Cepheids, and in the distant Universe done with Cosmic Microwave Background (CMB) imply different…