Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Effective action and vacuum expectations in nonlinear $\sigma$ model
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
17
The categories of this paper are: q-fin
4
The categories of this paper are: cond-mat
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
1
The categories of this paper are: cs