SOME PROPERTIES OF THE KERR SOLUTION TO LOW ENERGY STRING THEORY

TL;DR

This paper analyzes the Kerr solution within axidilaton gravity, showing it retains certain geometric properties but is not algebraically special, and connects it to heterotic string fields near singularities.

Contribution

It provides a detailed analysis of the axidilaton Kerr solution in the Debney--Kerr--Schild formalism and links it to heterotic string theory solutions.

Findings

Kerr principal null congruence remains geodesic and shear free.

The axidilaton Kerr solution is not algebraically special.

Near the singularity, the solution matches the field of a heterotic string.

Abstract

The Kerr solution to axidilaton gravity is analyzed in the Debney--Kerr--Schild formalism. It is shown that the Kerr principal null congruence retains its property to be geodesic and shear free, however, the axidilatonic Kerr solution is not algebraically special. A limiting form of this solution is considered near the ring-like Kerr singularity. This limiting solution coincides with the field around a fundamental heterotic string obtained by Sen.