Nonsupersymmetric Brane/Antibrane Configurations in Type IIA and M Theory

TL;DR

This paper investigates metastable nonsupersymmetric brane configurations in type IIA string theory and their M theory lifts, revealing how different coupling regimes affect the geometric and flux descriptions of the vacua.

Contribution

It provides an exact M theory lift for certain brane/antibrane setups and analyzes their properties across weak and strong coupling regimes, connecting to IIB flux geometries.

Findings

Exact M theory lift for brane/antibrane configurations.

Agreement between weak coupling M theory and IIB flux geometries.

Nonholomorphic minimal area curves at strong coupling suggest further supersymmetry breaking.

Abstract

We study metastable nonsupersymmetric configurations in type IIA string theory, obtained by suspending D4-branes and anti-D4-branes between holomorphically curved NS5's, which are related to those of hep-th/0610249 by T-duality. When the numbers of branes and antibranes are the same, we are able to obtain an exact M theory lift which can be used to reliably describe the vacuum configuration as a curved NS5 with dissolved RR flux for g_s<<1 and as a curved M5 for g_s>>1. When our weakly coupled description is reliable, it is related by T-duality to the deformed IIB geometry with flux of hep-th/0610249 with moduli exactly minimizing the potential derived therein using special geometry. Moreover, we can use a direct analysis of the action to argue that this agreement must also hold for the more general brane/antibrane configurations of hep-th/0610249. On the other hand, when our strongly coupled description is reliable, the M5 wraps a nonholomorphic minimal area curve that can exhibit quite different properties, suggesting that the residual structure remaining after spontaneous breaking of supersymmetry at tree level can be further broken by the effects of string interactions. Finally, we discuss the boundary condition issues raised in hep-th/0608157 for nonsupersymmetric IIA configurations, their implications for our setup, and their realization on the type IIB side.