Physical Properties of Four Dimensional Superstring Gravity Black Hole Solutions

TL;DR

This paper investigates the physical properties of four-dimensional black hole solutions within heterotic superstring theory, comparing perturbative, exact, and classical solutions, and discusses implications for tests of general relativity.

Contribution

It provides a comparative analysis of black hole solutions in string theory, highlighting differences from classical Einstein-Maxwell solutions and exploring their physical implications.

Findings

Differences between perturbative and exact string solutions.

Limitations of current analytical approaches.

Potential observable effects in classical tests of gravity.

Abstract

We consider the physical properties of four dimensional black hole solutions to the effective action describing the low energy dynamics of the gravitational sector of heterotic superstring theory. We compare the properties of the external field strengths in the perturbative solution to the full $O(\alpha')$ string effective action equations, to those of exact solutions in a truncated action for charged black holes, and to the Kerr-Newman family of solutions of Einstein-Maxwell theory. We contrast the numerical results obtained in these approaches, and discuss limitations of the analyses. Finally we discuss how the new features of classical string gravity affect the standard tests of general relativity.