Worldsheet instanton corrections to the Kaluza-Klein monopole

Abstract

The Kaluza-Klein monopole is a well known object in both gravity and string theory, related by T-duality to a ''smeared'' NS5-brane which retains the isometry around the duality circle. As the true NS5-brane solution is localized at a point on the circle, duality implies that the Kaluza-Klein monopole should show some corresponding behavior. In this paper, we express the Kaluza-Klein monopole as a gauged linear sigma model in two dimensions and show that worldsheet instantons give corrections to its geometry. These corrections can be understood as a localization in ''winding space'' which could be probed by strings with winding charge around the circle. © SISSA 2005.