BPS State Counting in N=8 Supersymmetric String Theory for Pure D-brane Configurations

TL;DR

This paper counts BPS states in N=8 string theory with pure D-brane configurations, confirming duality predictions and revealing that these states carry zero angular momentum after accounting for supermultiplet structure.

Contribution

It establishes a method for counting BPS states with pure D-brane charges in a duality frame and confirms their properties match black hole predictions.

Findings

Counting matches results from other duality frames.

States carry zero angular momentum after supermultiplet factoring.

Results support black hole state representations.

Abstract

Exact results for the BPS index are known for a class of BPS dyons in type II string theory compactified on a six dimensional torus. In this paper we set up the problem of counting the same BPS states in a duality frame in which the states carry only Ramond-Ramond charges. We explicitly count the number of states carrying the lowest possible charges and find agreement with the result obtained in other duality frames. Furthermore, we find that after factoring out the supermultiplet structure, each of these states carry zero angular momentum. This is in agreement with the prediction obtained from a representation of these states as supersymmetric black holes.