Extremal Branes as Elementary Particles

TL;DR

This paper demonstrates how extremal p-branes in string theory act like elementary particles by developing an infinite mass gap, preventing catastrophic instabilities and differentiating them from nonextremal black holes.

Contribution

It reveals the mechanism by which extremal branes avoid instability through an infinite mass gap, clarifying their particle-like behavior in string theory.

Findings

Extremal branes develop an infinite mass gap preventing absorption.

They behave like elementary particles dressed by effective potentials.

Nonextremal branes and intersecting configurations resemble conventional black holes.

Abstract

The supersymmetric p-branes of Type II string theory can be interpreted after compactification as extremal black holes with zero entropy and infinite temperature. We show how the p-branes avoid this apparent, catastrophic instability by developing an infinite mass gap. Equivalently, these black holes behave like elementary particles: they are dressed by effective potentials that prevent absorption of impinging particles. In contrast, configurations with 2, 3, and 4 intersecting branes and their nonextremal extensions, behave increasingly like conventional black holes. These results extend and clarify earlier work by Holzhey and Wilczek in the context of four dimensional dilaton gravity.