Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Pairs of surface wave packets with zero-sum energy in the Hawking
  radiation analog
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con