String-Loop Corrected Magnetic Black Holes

TL;DR

This paper investigates string-loop corrections to magnetic black hole solutions in heterotic string theory compactified on K3×T2, analyzing how quantum effects modify gauge couplings and potentially smooth out classical singularities.

Contribution

It computes loop corrections to gauge couplings and solutions in N=2 supersymmetric effective theories derived from heterotic string compactifications.

Findings

Loop corrections significantly affect gauge couplings at small distances.

Quantum effects may smooth out classical black hole singularities.

The study provides explicit solutions incorporating string-loop effects.

Abstract

We discuss the form of the string-loop-corrected effective action obtained by compactification of the heterotic string theory on the manifold $K3\times T^2$ or on its orbifold limit and the loop-corrected magnetic black hole solutions of the equations of motion. Effective 4D theory has N=2 local supersymmetry. Using the string-loop-corrected prepotential of the N=2 supersymmetric theory, which receives corrections only from the string world sheets of torus topology, we calculate the loop corrections to the tree-level gauge couplings and solve the loop-corrected equations of motion. At the string-tree level, the effective gauge couplings decrease at small distances from the origin, and in this region string-loop corrections to the gauge couplings become important. A possibility of smearing the singularity of the tree-level supersymmetric solution with partially broken supersymmetry by quantum corrections is discussed.