Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A Unified, Merger-Driven Model for the Origin of Starbursts, Quasars,
  the Cosmic X-Ray Background, Supermassive Black Holes and Galaxy Spheroids
37
The categories of this paper are: supr-con
2
The categories of this paper are: math
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph