Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Topological Charge and Black Hole Photon Spheres
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
2
The categories of this paper are: math
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org