Related papers: A cosmological concordance model with dynamical va…
The standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the Hubble constant $H_{0}$ and inferences of its values from Cosmic Microwave Background (CMB) anisotropies.…
Cosmic Microwave Background (CMB) anisotropy encodes a lot of information about our Universe. In this paper we take the ground-based CMB observations (GCMB), including the South Pole Telescope (SPT), SPTpol and the Atacama Cosmology…
We investigate cosmological solutions of Brans-Dicke theory with both the vacuum energy density and the gravitational constant decaying linearly with the Hubble parameter. A particular class of them, with constant deceleration factor, sheds…
A strictly linear evolution of the cosmological scale factor is surprisingly an excellent fit to a host of cosmological observations. Any model that can support such a coasting presents itself as a falsifiable model as far as classical…
The inability of primordial baryonic density fluctuations, as observed in the cosmic microwave background (CMB), to grow into the present day astronomical structures is well established, under Newtonian and Einsteinian gravity. It is hence…
We determine the range of parameter space of Interacting Quintessence Models that best fits the recent WMAP measurements of Cosmic Microwave Background temperature anisotropies. We only consider cosmological models with zero spatial…
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…
We focus on the class of cosmological models with a time-evolving vacuum energy density of the form $\rho_\Lambda=C_0+C_1 H+C_2 H^2$, where $H$ is the Hubble rate. Higher powers of $H$ could be important for the early inflationary epoch,…
The accelerating expansion of the universe is the most surprising cosmological discovery in many decades. In this short review, we briefly summarize theories for the origin of cosmic acceleration and the observational methods being used to…
Over the past decades, cosmology has become largely based on experimental data, the most important sources of which are studies of the cosmic microwave background (CMB). CMB is present in the Universe since the very first moments of its…
We investigate the evolution of a universe with a decaying cosmological term (vacuum energy) that is assumed to be a function of the scale factor. In this model, while the cosmological term increases to the early universe, the radiation…
A spherical cosmological model with a local void on scales of $\sim 200$ Mpc and with an inhomogeneous Hubble constant was proposed in recent two papers. This model explains consistently the observed properties of the cosmic bulk flow, the…
We test the theoretical predictions of several cosmological models against different observables to compare the indirect estimates of the current expansion rate of the Universe determined from model fitting with the direct measurements…
A simple model of uniformly expanding, homogeneous Universe with a bulk viscosity is studied wherein the inflationary density decays due to viscous dissipation during the expansion phase of the Universe. The model is shown to generate the…
The current suite of results from Cosmic Microwave Background anisotropy experiments is fulfilling the promise of providing extraordinary levels of discrimination between cosmological models. We calculate a binned anisotropy power spectrum,…
The last years have been an exciting period for the field of the Cosmic Microwave Background (CMB) research. With recent CMB balloon-borne and ground-based experiments we are entering a new era of 'precision' cosmology that enables us to…
We have witnessed different values of the Hubble constant being found in the literature in the past years. Albeit, early measurements often result in an $H_0$ much smaller than those from late-time ones, producing a statistically…
The concordance of the $\Lambda$CDM cosmological model in light of current observations has been the subject of an intense debate in recent months. The 2018 Planck Cosmic Microwave Background (CMB) temperature anisotropy power spectrum…
Recent observations of the cosmic microwave background (CMB) and baryon acoustic oscillations (BAO) show some tension with a $\Lambda$CDM cosmology. For one, the cosmological parameters determined by the CMB are at odds with the expansion…
This is a course on cosmic microwave background (CMB) anisotropies in the standard cosmological model, designed for beginning graduate students and advanced undergraduates. ``Standard cosmological model'' in this context means a Universe…