Near-horizon microstructure and superradiant instability of black holes

Understand

Ultralight bosons, as important candidates of dark matter, can condense around spinning black holes (BHs) to form long-lived ``boson clouds'' due to superradiance instability.

• The boson-BH system can be observed through gravitational wave detection and may become a new window to find traces of ultralight bosons.
• In this letter we explore the effects on the superradiant instability of BHs from the near-horizon microstructure.
• By introducing the reflection parameter near a BH horizon, we derived analytical results on the corrections to both energy levels of bosonic cloud and its characteristic frequencies of superradiance instability.