Four-modulus "Swiss Cheese" chiral models

TL;DR

<3-5 sentence high-level summary> The paper investigates moduli stabilization using the Large Volume Scenario on explicit four-modulus Calabi–Yau manifolds in type IIB string theory, focusing on the chirality problem generated by intersecting D7-branes. It develops a framework that accounts for the Freed-Witten anomaly and carefully counts neutral and charged instanton zero-modes to ensure neutral E3 contributions to the superpotential, while avoiding unwanted charged zero-modes. Through explicit toric geometry scans, it identifies Swiss cheese CYs with a large cycle and several small shrinkable cycles, and builds local and global D-brane configurations, including Whitney-type hidden branes, to realize LVS under stringent global constraints. The results show that LVS can be compatible with chirally intersecting D7-branes in some four-modulus models, achieving up to three moduli stabilization, and highlight the advantage of Whitney-type branes for satisfying global constraints and achieving sizable D3-charge.

Abstract

We study the 'Large Volume Scenario' on explicit, new, compact, four-modulus Calabi-Yau manifolds. We pay special attention to the chirality problem pointed out by Blumenhagen, Moster and Plauschinn. Namely, we thoroughly analyze the possibility of generating neutral, non-perturbative superpotentials from Euclidean D3-branes in the presence of chirally intersecting D7-branes. We find that taking proper account of the Freed-Witten anomaly on non-spin cycles and of the Kaehler cone conditions imposes severe constraints on the models. Nevertheless, we are able to create setups where the constraints are solved, and up to three moduli are stabilized.