D-Branes and Bundles on Elliptic Fibrations

TL;DR

This paper explores the D-brane spectrum on a Calabi-Yau model with elliptic fibrations, establishing a correspondence between geometric and conformal field theory descriptions, and revealing novel stability phenomena in string theory.

Contribution

It develops an explicit link between wrapped brane configurations and boundary states, suggesting boundary states as quantum generalizations of bundles, and uncovers stability changes of D-branes in stringy regimes.

Findings

Boundary states are natural quantum generalizations of bundles.

Nonsupersymmetric D-branes become stable at the Gepner point.

New D-brane dynamics observed in deep stringy regimes.

Abstract

We study the D-brane spectrum on a two-parameter Calabi-Yau model. The analysis is based on different tools in distinct regions of the moduli space: wrapped brane configurations on elliptic fibrations near the large radius limit, and SCFT boundary states at the Gepner point. We develop an explicit correspondence between these two classes of objects, suggesting that boundary states are natural quantum generalizations of bundles. We also find interesting D-brane dynamics in deep stringy regimes. The most striking example is, perhaps, that nonsupersymmetric D6-D0 and D4-D2 large radius configurations become stable BPS states at the Gepner point.