Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Cosmic opacity: cosmological-model-independent tests and their impacts
  on cosmic acceleration
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom