Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Supermassive Black Holes in Elliptical Galaxies: Switching from Very
  Bright to Very Dim
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
16
The categories of this paper are: stat
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg