Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Characterization of the lack of compactness of $H^2_{rad}(\R^4)$ into
  the Orlicz space
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
0
The categories of this paper are: hep-ph
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
8
The categories of this paper are: hep-ex
32
The categories of this paper are: atom-ph