Related papers: COBE-DMR-Normalized Dark Energy Cosmogony
Popular extensions of the standard model of particle physics feature new fields and symmetries which could, for example, dynamically generate neutrino masses from $B-L$ spontaneous symmetry breaking. If a new light scalar that decays into…
The cosmic microwave background radiation provides unique constraints on cosmological models. In this Letter we present a summary of the spatial properties of the cosmic microwave background radiation based on the full 4 years of COBE DMR…
We present an approach to the problem of vacuum energy in cosmology, based on dynamical screening of Lambda on the horizon scale. We review first the physical basis of vacuum energy as a phenomenon connected with macroscopic boundary…
For dynamical dark energy with the barotropic equation of state we determine the mean values of parameters and their confidence ranges together with other cosmological parameters on the basis of different combined datasets. The used…
Over the last decades, tests on the standard model of cosmology, the so-called $\Lambda$CDM model, have been widely analysed and compared with many different models for describing dark energy. Modified gravities have played an important…
We have made a likelihood statistical analysis of the angular correlations in the {\it COBE}-DMR two-year sky maps by Monte Carlo simulation of the temperature fluctuations. We assume an open universe and consider as primordial power…
We compare a large set of cosmologies with WMAP data, performing a fit based on a MCMC algorithm. Besides of LCDM models, we take dynamical DE models, where DE and DM are uncoupled or coupled, both in the case of constant coupling and in…
While a scalar field with a pole in its kinetic term is often used to study the cosmological inflation, it can also play the role of dark energy, which is called the pole dark energy model. We propose a generalized model that the scalar…
There is now strong evidence that the current energy density of the Universe is dominated by dark energy with an equation of state w<-1/3, which is causing accelerated expansion. The build-up of structure within such Universes is subject to…
A non-trivial spatial topology of the Universe is a potentially observable attribute, which can be probed through the circles-in-the-sky for all locally homogeneous and isotropic universes with no assumptions on the cosmological parameters.…
We discuss the evolution of density perturbations of dark matter and dark energy in cosmological models which admit future singularities in a finite time. Up to now geometrical tests of the evolution of the universe do not differentiate…
We review a subset of the current tensions affecting the standard $\Lambda$CDM cosmological model, emphasizing the role of chronic systematics and significance inflation in shaping their interpretation. As a unifying framework, we consider…
We consider a model where both dark energy and dark matter originate from the coupling of a scalar field with a non-conventional kinetic term to, both, a metric measure and a non-metric measure. An interacting dark energy/dark matter…
Standard cosmological data analyses typically constrain simple phenomenological dark-energy parameters, for example the present-day value of the equation of state parameter, $w_0$, and its variation with scale factor, $w_a$. However,…
We use late Universe probes - Type Ia Supernovae from the PantheonPlus compilation, Quasars, and Dark Energy Spectroscopic Instrument (DESI) Data Release 1 (DR1) BAO data - along with Cosmic Chronometers or Megamasers to constrain various…
We study the spherical collapse model in dark energy cosmologies, in which dark energy is modelled as a minimally coupled scalar field. We first follow the standard assumption that dark energy does not cluster on the scales of interest.…
A novel fractal structure for the cosmological horizon, inspired by COVID-19 geometry, which results in a modified area entropy, is applied to cosmology in order to serve dark energy. The constraints based on a complete set of observational…
The standard model of cosmology assumes that the Universe can be described to hover around a homogeneous-isotropic solution of Einstein's general theory of relativity. This description needs (sometimes hidden) hypotheses that restrict the…
We investigate the prospect of constraining scalar field dark energy models using HI 21-cm intensity mapping surveys. We consider a wide class of coupled scalar field dark energy models whose predictions about the background cosmological…
We consider the Eddington-Born-Infeld (EBI) model here without assuming any cosmological constant. The EBI scalar field is supposed to play a role of both dark matter and dark energy. Different eras in cosmology are reconstructed for the…