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arXiv · hep-th/9402073

Exact Supersymmetric String Solutions in Curved Gravitational Backgrounds

I. Antoniadis·S. Ferrara·C. Kounnas
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Abstract

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 $5\le{\hat c}_M\le 9$.

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I. Antoniadis, S. Ferrara, C. Kounnas. 1994-03-01. Exact Supersymmetric String Solutions in Curved Gravitational Backgrounds. https://doi.org/10.1016/0550-3213(94)90331-x

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