Stability and Negative Tensions in 6D Brane Worlds

TL;DR

This paper analyzes the stability of 6D brane world models with conical defects, revealing that negative tension branes can relax stability constraints compared to positive tension cases.

Contribution

It provides a detailed stability analysis of warped 6D supergravity compactifications with conical defects, highlighting the role of brane tensions and anomaly-related fields.

Findings

Positive tension branes require strict stability conditions similar to sphere compactifications.

Negative tension branes can relax stability criteria, allowing more model configurations.

Detailed geometries of negative tension codimension two branes are described.

Abstract

We investigate the dynamical stability of warped, axially symmetric compactifications in anomaly free 6D gauged supergravity. The solutions have conical defects, which we source by 3-branes placed on orbifold fixed points, and a smooth limit to the classic sphere-monopole compactification. Like for the sphere, the extra fields that are generically required by anomaly freedom are especially relevant for stability. With positive tension branes only, there is a strict stability criterion (identical to the sphere case) on the charges present under the monopole background. Thus brane world models with positive tensions can be embedded into anomaly free theories in only a few ways. Meanwhile, surprisingly, in the presence of a negative tension brane the stability criteria can be relaxed. We also describe in detail the geometries induced by negative tension codimension two branes.