Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Controllability and Observability of Multi-Spin Systems: Constraints by
  Symmetry and by Relaxation
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ