Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Quantum ergodicity for expanding quantum graphs in the regime of
  spectral delocalization
10
The categories of this paper are: q-bio
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
16
The categories of this paper are: stat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
9
The categories of this paper are: nlin
17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom