Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Search for an exotic three-body decay of orthopositronium
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int