Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Global properties of an exact string theory solution in two and four
  dimensions   This paper discusses global properties of exact (in alpha prime) string
theory solutions: A deformed black hole solution in two dimensions and a
Taub-NUT type solution in four dimensions. These models are exact by virtue of
having CFT descriptions in terms of heterotic coset models. The analysis
includes analytic continuations of the metric, motion of test particles, and
the T-duality which acts as a map between different regions of the extended
solutions, rendering the physical spacetimes non-singular.

21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg