Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: General relativistic hydrodynamics with viscosity: contraction,
  catastrophic collapse, and disk formation in hypermassive neutron stars
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
2
The categories of this paper are: math
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys