Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Electromagnetic and weak current operators for interacting systems
  within the front-form dynamics
14
The categories of this paper are: math-ph
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
28
The categories of this paper are: alg-geom
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol