Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nodal compact $Q$-ball/$Q$-shell in the $\mathbb{C}P^N$ nonlinear sigma
  model   Nodal, excited compactons in the $\mathbb{C}P^N$ models with V-shaped
potentials are analyzed. It is shown that the solutions exist as compact
$Q$-balls and $Q$-shells. The solutions have a discontinuity in the second
derivative associated with the character of the potential, however, their
energy and charge densities are both continuous. The excited $Q$-balls and
$Q$-shells are analyzed as electrically neutral and electrically charged
objects.

22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
2
The categories of this paper are: math
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
3
The categories of this paper are: physics
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
33
The categories of this paper are: plasm-ph