Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Formation of Spiral Structures in Galactic Discs from Reaction-Diffusion
  Networks
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
4
The categories of this paper are: cond-mat