Cosmology

Coordinator: David Polarski

Cosmology experienced a dramatic evolution in the last decades due to a very large amount of observational data of ever-increasing accuracy. A consistent picture has emerged from the initial Big Bang till today’s accelerated expansion of our Universe with the so-called Concordance model. We have worked on various aspects of inflationary models – which generate all large-scale structures – and their observational constraints.

We have also considered the fundamental problem of the quantum-to-classical transition of the cosmic perturbations produced during inflation out of vacuum quantum fluctuations. The present-day accelerated expansion of the universe or Dark Energy models is another field on which we have been working. In particular we have proposed in 2000 a parameterization of the Dark Energy equation of state parameter which is largely used by the community and by all large experimental collaborations.  We have also considered -modified gravity Dark Energy models namely scalar-tensor and f(R) models. More recently we have been working on possible extensions of the Concordance model.