Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The multiple solutions of self-consistency condition in Walecka model
  and the validity of the Brown-Rho scaling law
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
6
The categories of this paper are: astro-ph
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org