Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Pion mass difference from vacuum polarization
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
18
The categories of this paper are: econ
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an