Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: A Classification of subgroups of SL(4,R) Isomorphic to R^3 and
  Generalized Cusps in Projective 3 Manifolds
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
20
The categories of this paper are: acc-phys