Bound states in N=2 Liouville theory with boundary and Deep throat D-branes

TL;DR

This paper identifies bound states of non-compact D-branes in N=2 Liouville theory, linking them to phenomena in string theory near NS5-branes and revealing their role in low-energy gauge theories.

Contribution

It demonstrates the existence of bound states in N=2 Liouville theory with boundary, connecting conformal field theory results to D-brane dynamics near NS5-branes.

Findings

Bound states exist in the spectrum of non-compact D-branes.

Bound states can produce massless multiplets in low-energy theories.

Semi-classical effects match exact conformal field theory results.

Abstract

We exhibit bound states in the spectrum of non-compact D-branes in N=2 Liouville conformal field theory. We interpret these states in the study of D-branes in the near-horizon limit of Neveu-Schwarz five-branes spread on a topologically trivial circle. We match semi-classical di-electric and repulsion effects with exact conformal field theory results and describe the fate of D-branes hitting NS5-branes. We also show that the bound states can give rise to massless vector and hyper multiplets in a low-energy gauge theory on D-branes deep inside the throat.