Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Relativistic Topological Insulator Model   A relativistic topological insulator model in three spatial dimensions which
is a non trivial extension of the non-abelian Landau problem is proposed. The
model is exactly soluble and energy levels have both a discrete and a
continuous degeneracy. The chromomagnetic field is strong and the fermions are
confined in a plane and the physical effects that appear reflects the ${\bm
Z}_2$ symmetry.

14
The categories of this paper are: math-ph
35
The categories of this paper are: mtrl-th
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin