A class of non-singular gravi-dilaton backgrounds

TL;DR

This paper introduces a class of non-singular, static, spherically symmetric solutions in string theory that interpolate between two anti-de Sitter spaces, highlighting the role of finite-size $'$ corrections in avoiding singularities.

Contribution

It provides explicit non-singular solutions in string theory with finite dilaton coupling, emphasizing the significance of ' corrections in resolving space-time singularities.

Findings

Solutions interpolate between two anti-de Sitter configurations.

Dilaton remains finite and controllably small.

Finite ' corrections can prevent space-time singularities.

Abstract

We present a class of static, spherically symmetric, non-singular solutions of the tree-level string effective action, truncated to first order in $\alpha'$. 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 $\alpha'$ corrections, typical of string theory, in avoiding space-time singularities.