Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pair production of black holes on cosmic strings   We discuss the pair creation of black holes by the breaking of a cosmic
string. We obtain an instanton describing this process from the $C$ metric, and
calculate its probability. This is very low for the strings that have been
suggested for galaxy formation.

37
The categories of this paper are: supr-con
3
The categories of this paper are: physics
11
The categories of this paper are: hep-lat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph