Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Lattice determination of the pion mass difference $M_{\pi^{+}} -
  M_{\pi^{0}}$ at order $\mathcal{O}(\alpha_{em})$ and $\mathcal{O}(
  (m_{d}-m_{u})^{2})$ including disconnected diagrams
3
The categories of this paper are: physics
12
The categories of this paper are: nucl-th
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
1
The categories of this paper are: cs
13
The categories of this paper are: quant-ph
15
The categories of this paper are: nucl-ex
21
The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ