THE EVOLUTION OF BINARY SYSTEMS IN GASEOUS ENVIRONMENTS

Systems where a binary, that is two gravitationally bound objects orbiting their centre of mass, interacts with the surrounding gas or dust are extremely common in the Universe and involve a wide variety of different astrophysical objects (star + star, black hole + black hole, star + planet, or planet + moon). Among them, protoplanetary systems and black hole binaries (BHBs) are currently capturing the attention of the scientific community. Despite their very different nature and EM appearance, both protoplanetary and BHB systems are characterized by the presence of a gaseous accretion disc surrounding the binary. As a consequence, the dynamics of these systems is very similar and can be described in one unique theoretical framework: the disc-satellite interaction theory. This project is meant to deepen our knowledge of the theory of circumbinary discs, approaching it in a multidisciplinary way from both the protoplanetary and the BHBs perspective.