Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Hybrid $SU(2)\times U(1)$ models, electric charge nonconservation and
  the photon mass
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
14
The categories of this paper are: math-ph
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
1
The categories of this paper are: cs
2
The categories of this paper are: math
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
29
The categories of this paper are: funct-an