Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A note on minimization of rational surfaces obtained from birational
  dynamical systems
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex