Related papers: Boomerang returns unexpectedly
An oscillating universe cycles through a series of expansions and contractions. We propose a model in which ``phantom'' energy with $p < -\rho$ grows rapidly and dominates the late-time expanding phase. The universe's energy density is so…
Cosmological theories for the origin and evolution of structure in the Universe are highly predictive of the form of the angular power spectrum of cosmic microwave background fluctuations. We present new results from a comprehensive study…
It is commonly assumed that the stochastic background of gravitational waves on cosmological scales follows an almost scale-independent power spectrum, as generically predicted by the inflationary paradigm. However, it is not inconceivable…
In forthcoming years, connections between cosmology and particle physics will be made increasingly important with the advent of a new generation of cosmic microwave background (CMB) experiments. Here, we review a number of these links. Our…
Inflationary cosmology has proved to be the most successful at predicting the properties of the anisotropies observed in the cosmic microwave background (CMB). In this essay we show that quantum field renormalization significantly…
Classical and quantum gravitational instabilities, can, respectively, inflate and warm up a primordial Universe satisfying a superstring-motivated principle of "Asymptotic Past Triviality". A physically viable big bang is thus generated…
We argue that the lack of power exhibited by cosmic microwave background (CMB) anisotropies at large angular scales might be linked to the onset of inflation. We highlight observational features and theoretical hints that support this view,…
A conventional explanation of the dipole anisotropy of the cosmic microwave background (CMB) radiation is in terms of the Doppler effect: our galaxy is moving with respect to CMB frame with $ \sim 600 ~ km ~ s^{-1} $. However, as the deep…
Recent measurements of temperature fluctuations in the cosmic microwave background (CMB) indicate that the Universe is flat and that large-scale structure grew via gravitational infall from primordial adiabatic perturbations. Both of these…
Anisotropies in the Cosmic Microwave Background (CMB) contain a wealth of information about the past history of the universe and the present values of cosmological parameters. I ouline some of the theoretical advances of the last few years.…
We expose the scenarios of primordial baryon-photon plasma evolution within the framework of the Milne-like universe models. Recently, such models find a second wind and promise an inflation-free solution of a lot of cosmological puzzles…
Interest in non-standard recombination scenarios has been spurred by recent cosmic microwave background (CMB) results from BOOMERANG and MAXIMA, which show an unexpectedly low second acoustic peak, resulting in a best-fit baryon density…
With the era of precision cosmology upon us, and upcoming surveys expected to further improve the precision of our observations below the percent level, ensuring the accuracy of our theoretical cosmological model is of the utmost…
We devise a measure n(r) to quantify a robust feature in the coherent cosmic perturbations, namely the narrowness of the first peak in the power spectrum of the Cosmic Microwave Background (CMB) anisotropy. A maximum-likelihood analysis…
With the recent publication of the measurements of the radiation angular power spectrum from the BOOMERanG Antarctic flight (de Bernardis et al. 2000), it has become apparent that the currently favoured spatially-flat cold dark matter model…
We point out that the recent WMAP findings of a suppressed large scale power in the Cosmic Microwave Background anisotropy power spectrum, if of cosmological origin, make the case for a new cosmic coincidence problem.The observed…
The cosmic microwave background (CMB), the relic radiation from the early Universe, offers a unique window into both primordial conditions and the intervening large-scale structure (LSS) it traverses. Interactions between CMB photons and…
Recent data suggest that the Universe could be positively curved. Combined with an inflationary stage, this might lead to a curvature bounce instead of the Big Bang. The background evolution is presented, as a function of the parameters…
We present a possible understanding to the issues of cosmological constant, inflation, matter and coincidence problems based only on the Einstein equation and Hawking particle production. The inflation appears and results agree to…
Cosmic microwave background (CMB) anisotropy may result from both scalar and tensor perturbations. For a sufficiently narrow range of angular scales, CMB perturbations can be characterized by four parameters. Results from the Cosmic…