Massive String States as Extreme Black Holes

TL;DR

This paper links certain massive string states in heterotic string theory to extreme black hole solutions, showing a correspondence between their spectrum and black hole characteristics, and explores dual descriptions via scalar-Maxwell theories.

Contribution

It demonstrates that specific massive string states correspond to extreme black holes and provides a unified description using scalar-Maxwell theories with different parameters.

Findings

Maximum spin supermultiplets match extreme black hole solutions

Scalar-Maxwell descriptions with specific parameters apply to different states

S-duality relates magnetically charged spectrum to extreme black holes

Abstract

We consider the Schwarz-Sen spectrum of elementary electrically charged massive $N_R=1/2$ states of the four-dimensional heterotic string and show the maximum spin $1$ supermultiplets to correspond to extreme black hole solutions. The $N_L=1$ states and $N_L>1$ states (with vanishing left-moving internal momentum) admit a single scalar-Maxwell description with parameters $a=\sqrt 3$ or $a=1$, respectively. The corresponding solitonic magnetically charged spectrum conjectured by Schwarz and Sen on the basis of $S$-duality is also described by extreme black holes.