Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Near-horizon microstructure and superradiant instability of black holes   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. Our results imply that the evolution
of a boson-BH system and gravitational waves it emits would be influenced by
the near-horizon physics of a BH.

3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an