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arXiv · hep-th/9707053

A class of non-singular gravi-dilaton backgrounds

A. Buonanno·M. Gasperini·C. Ungarelli
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Abstract

We present a class of static, spherically symmetric, non-singular solutions of the tree-level string effective action, truncated to first order in $α'$. In the string frame the solutions approach asymptotically (at $r\to 0$ and $r\to \infty$) two different anti-de Sitter configurations, thus interpolating between two maximally symmetric states of different constant curvature. The radial-dependent dilaton defines a string coupling which is everywhere finite, with a peak value that can be chosen arbitrarily small so as to neglect quantum-loop corrections. This example stresses the possible importance of finite-size $α'$ corrections, typical of string theory, in avoiding space-time singularities.

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A. Buonanno, M. Gasperini, C. Ungarelli. 1997-07-04. A class of non-singular gravi-dilaton backgrounds. https://doi.org/10.1142/s021773239700193x

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