Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On a problem of dark matter: A centrally symmetric distribution of a
  pseudoscalar field in the general relativity   A precise solution of the general relativity equations for centrally
symmetric distribution of a pseudoscalar field with U(1) symmetry is presented.
It is found that energy density of the field is restricted in the symmetry
center and falls with radial distance at a much slower rate than in numerical
simulations of dark matter haloes. This result can solve the cusp problem for
galaxies and the problem of rotation curves for galaxy exteriors.

30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
22
The categories of this paper are: chao-dyn
14
The categories of this paper are: math-ph
31
The categories of this paper are: ao-sci
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys