Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Canonical Thurston Obstructions for Sub-Hyperbolic Semi-Rational
  Branched Coverings
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
30
The categories of this paper are: q-alg
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex