Supersymmetric embedding of antibrane polarization

TL;DR

This paper develops a supersymmetric effective model for antibrane polarization in a string theory background, revealing the spectrum of fluctuations and implications for de Sitter vacua and inflation.

Contribution

It introduces a manifestly supersymmetric model that captures the metastable supersymmetry-breaking state via polarization and Kaluza-Klein modes in a string theory setting.

Findings

Identifies the Goldstino in the polarized metastable state.

Calculates the spectrum of massive Kaluza-Klein fluctuations.

Shows how supersymmetry is nonlinearly realized below the Kaluza-Klein scale.

Abstract

We study the supersymmetry breaking induced by probe anti-D3-branes at the tip of the Klebanov-Strassler throat geometry. Antibranes inside this geometry polarize and can be described by an NS5-brane wrapping an $S^2$. When the number of antibranes is small compared to the background flux a metastable state exists that breaks supersymmetry. We present a manifestly supersymmetric effective model that realizes the polarized metastable state as a solution, spontaneously breaking the supersymmetry. The supersymmetric model relies crucially on the inclusion of Kaluza-Klein (matrix) degrees of freedom on the $S^2$ and two supersymmetric irrelevant deformations of ${\cal N}=4$ super-Yang-Mills (SYM), describing a large number of supersymmetric D3-branes in the IR. We explicitly identify the massless Goldstino and compute the spectrum of massive fluctuations around the metastable supersymmetry-breaking minimum, finding a Kaluza-Klein tower with masses warped down from the string scale. Below the Kaluza-Klein scale the massive tower can be integrated out and supersymmetry is realized nonlinearly. We comment on the effect of the Kaluza-Klein modes on the effective description of de Sitter vacua in string theory and inflationary model building.