Towards a physics of society

Statistical physics has proven to be an invaluable tool to describe and understand the properties of systems formed by a large number of elementary units. A big challenge is whether the tools and techniques of statistical physics are suitable to explore large scale social phenomena. Most attempts of the literature focus on simple microscopic models, with little or no contact to real social dynamics. A validation of this approach is still lacking and must rely on quantitative evidence about real social systems. Finding regularities on real data is a crucial step in this direction. We will show that voting and citing behaviors are both characterized by scaling and universality. The statistical distribution of the number of votes/cites, suitably normalized, is independent of the particular system considered. This opens the way to a simple modeling of the observed phenomenology.