Black holes and fundamental fields: hair, kicks and a gravitational "Magnus" effect

Understand

Scalar fields pervade theoretical physics and are a fundamental ingredient to solve the dark matter problem, to realize the Peccei-Quinn mechanism in QCD or the string-axiverse scenario.

• They are also a useful proxy for more complex matter interactions, such as accretion disks or matter in extreme conditions.
• Here, we study the collision between scalar "clouds" and rotating black holes.
• For the first time we are able to compare analytic estimates and strong field, nonlinear numerical calculations for this problem.