Description
Title: Common Envelope Evolution of Ultralight Boson Clouds
Abstract: Ultralight bosons, as potential dark matter candidates, can form dense clouds around black holes via superradiant instabilities. In binary black hole systems, these clouds evolve under mutual tidal interactions, and form a shared structure that envelopes the entire binary—termed a gravitational molecule —as orbital separation approaches the size of the cloud. We investigate the dynamics of ultralight boson cloud common envelopes, with non-adiabatic evolution driven by orbital eccentricity and energy-level crossings of gravitational molecules in comparable-mass black hole binaries. And this interaction induces significant backreaction on the binary's orbital parameters, accelerating/decelerating the inspiral and imprinting distinct phase shifts in gravitational wave signals.
