Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Exact Casimir interaction of perfectly conducting three-spheres in four
  euclidean dimensions
22
The categories of this paper are: chao-dyn
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
18
The categories of this paper are: econ