Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stability of black holes in f(R) gravity   We investigate the stability of black holes in the viable model of
$f(R)=R+R^2$ gravity which was known to be the best fit for inflation. These
include Schwarzschild and Kerr black holes. Instead of studying the
fourth-order linearized equation around the black hole background, we use the
corresponding tensor-scalar theory of the Starobinsky model to perform their
stability. The Schwarzschild black hole is stable, while the Kerr black hole is
unstable because of superradiant instability.

21
The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci