Cosmology is the study of the large scale structure of the Universe, as well as its dynamics. Our group has been involved in the study and development of cosmological models, in particular to explain the accelerated phases of the cosmological evolution, dubbed inflationary phases.
For our latest developments/activities in this area, please see the listing below.
Axions can play very important roles in cosmology. They are interesting candidates for dark matter, dark energy, inflation but also, in the case of the QCD axion, a natural solution to the strong CP problem.
The reduced phase space quantization of a closed Friedmann Universe is described. Its matter content is constituted by a specific perfect fluid. It is shown that, for this particular model, specific boundary conditions can be related to the algebra of Dirac observables.
Gr@v member Valério Ribeiro was part of an international team of researchers studying thermonuclear eruptions in the Andromeda galaxy. The team published, in Nature magazine, the discovery of a super-nova remnant which is bigger than most supernova remnants. They found that the super-nova remnant was the consequence of yearly repeated eruptions over millions of years. Few of these systems are known in the galaxy due to the fact that we suffer from dust obscuration.
One well known problem of the standard cosmological constant model is the tension between the high level of clustering observed in the CMB and the one obtained from large-scale structures. This may be an indication that the way dark energy affects clustering might differ from a simple cosmological constant.