Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: The rational stable homology of mapping class groups of universal
  nil-manifolds
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
13
The categories of this paper are: quant-ph
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th