Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Third order perturbations of a zero-pressure cosmological medium: Pure
  general relativistic nonlinear effects
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
2
The categories of this paper are: math
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
27
The categories of this paper are: comp-gas