Scalar field dynamics around black holes: superradiant instabilities and binary evolution

Understand

In classical general relativity astrophysical black holes can be affected by the superradiant instability when gravity is minimally coupled to a light bosonic field.

• The majority of phenomenological studies have focused on the idealized case in which the black hole is initially surrounded by a single mode superradiant seed.
• By studying the evolution of a scalar field with multiple modes initial data in a quasiadiabatic approximation, we show that the dynamics is more involved and depend on the initial seed energy and the amplitude ratio between the modes.
• We also present preliminary results of the dynamical evolution of a massive scalar field around a Newtonian and a fully relativistic, black hole binary.