Opening

• Giovanni La Rana (NA)
• Leonardo Merola (NA)

Room: Aula Caianiello Saluti del direttore della sezione di Napoli dell'INFN, Giovanni la Rana, e del direttore del Dipartimento di Fisica "Ettore Pancini", Leonardo Merola.

The concordance model of cosmology after Planck

• Gabriele Veneziano (Collège de France and CERN)

Room: Aula Caianiello I will start by reviewing why we need to abandon the old Hot Big Bang scenario in favor of a new, broadly-defined, inflationary paradigm. I will then argue that, in the absence of quantum mechanics, inflation would not be a viable alternative to the old paradigm and briefly review the mechanism by which a calculable spectrum of cosmological perturbations of quantum origin is generated.

Big bang or Big Bounce?

• Gabriele Veneziano (Collège de France and CERN)

Room: Aula Caianiello I will first illustrate the successes of the particular implementation of the inflationary idea known as slow-roll inflation. I will then illustrate a possible alternative to slow-roll inflation suggested by string theory. A comparison of the relative merits of those two implementations of the inflationary paradigm will conclude the early-cosmology part of the course.

Inhomogeneities and precision cosmology

• Gabriele Veneziano (Collège de France and CERN)

Room: Aula Caianiello I will discuss the way in which inhomogeneities in the recent and present Universe may affect the determination of basic cosmological parameters. A new adapted coordinate system simplifies considerably the study of light-like signals propagating in an inhomogeneous Universe. I will illustrate this on the so-called Hubble (redshift vs. distance) diagram claiming that inhomogeneities cannot replace dark energy as an explanation for cosmic acceleration. I will conclude with the amusing example of calculating time-of-flight differences for ultra relativistic particles propagating in a non-homogeneous Universe.