Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exact Supersymmetric String Solutions in Curved Gravitational
  Backgrounds   We construct a new class of exact and stable superstring solutions based on
$N=4$ superconformal world-sheet symmetry. In a subclass of these, the full
spectrum of string excitations is derived in a modular-invariant way. In the
weak curvature limit, our solutions describe a target space with non-trivial
metric and topology, and generalize the previously known (semi) wormhole. The
effective field theory limit is identified in certain cases, with solutions of
the $N=4$ and $N=8$ extended gauged supergravities, in which the number of
space-time supersymmetries is reduced by a factor of 2 because of the presence
of non-trivial dilaton, gravitational and/or gauge backgrounds. In the context
of string theory, our solutions correspond to stable non-critical superstrings
in the strong coupling region; the super-Liouville field couples to a unitary
matter system with central charge $5\le{\hat c}_M\le 9$.

21
The categories of this paper are: adap-org
2
The categories of this paper are: math
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol