Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Friedmann Limit of a point mass universe (is not
  Friedmann):Gravinational Lens Effect
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
4
The categories of this paper are: cond-mat
11
The categories of this paper are: hep-lat
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat