Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Signatures of Modified Gravity on the 21-cm Power Spectrum at
  Reionisation
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
36
The categories of this paper are: cmp-lg
24
The categories of this paper are: dg-ga
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
37
The categories of this paper are: supr-con