Massimo Capaccioli

MC photo

Massimo Capaccioli is an Italian astrophysicist, currently professor emeritus at the University of Naples Federico II. A student of Gérard de Vaucouleurs, he was mainly concerned with the dynamics and evolution of stellar systems and observational cosmology. As director of the Capodimonte Astronomical Observatory in Naples, he conceived and managed the construction of the VLT Survey Telescope (VST), in synergy with the European Southern Observatory. He chaired the Italian Astronomical Society for a decade, founding a quarterly Arabic-language journal. A journalist and passionate publicist, he is the author of university textbooks and books on popularization and history of science. A Commander of the Italian Republic for scientific merit (2005), he has received four honorary degrees from foreign universities.

Title of Talk

"Galaxy scaling relations: review and perspectives"


"Scaling relations are strong empirical or semi-empirical correlations found among observational/physical properties of galaxies such as mass, size, luminosity, colors and kinematical parameters. We may understand their importance in charactering and understanding galaxy structure, formation and evolution, by looking at the role played by a historical scale relation, Kepler's third law, in validating Newton's theory of gravitation. Galaxy scale relations are litmus tests and fine-tuning knobs for hydrodynamics or semi-analytic models of galaxies, tools to estimate galaxy distances, a way to discover new physical relationships, and much more. In this lecture, we shall review the subject from the methodological point of view, analyzing in particular the three main characteristics of scale relations (slope, intercept, and scatter) in the context of Ockham’s razor. We shall present the results so far achieved and their consequence in our understanding of galaxies by connecting the observed scale relations with the physical mechanisms behind them. Finally, we will throw our eye into the near future to try to see what is around the corner in this field of research. "