Moduli stabilization and supersymmetry breaking in effective theories of strings

TL;DR

This paper explores the landscape of string theory moduli in the most realistic region, revealing a structure where supersymmetry breaking occurs with a flat potential direction and heavy other moduli, consistent with weak scale SUSY breaking.

Contribution

It provides a model-independent analysis of moduli stabilization and supersymmetry breaking in the central region of string theory landscape, highlighting the potential structure and minima.

Findings

Superpotential has a fourth order zero in the SUSY breaking direction.

The potential is steep in SUSY preserving directions and flat in SUSY breaking directions.

Additional minima with large negative cosmological constant are likely.

Abstract

The region of moduli space of string theories which is most likely to describe the "real world" is where the string coupling is about unity and the volume of extra compact dimensions is about the same size as the string volume. Here we map the landscape of this "central" region in a model-independent way, assuming only that the string coupling and compact volume moduli are chiral superfields of N=1 supergravity in 4 dimensions, and requiring only widely accepted conditions: that the supersymmetry (SUSY) breaking scale is about the weak scale and that the cosmological constant be of acceptably small magnitude. We find that the superpotential has (in the supersymmetric limit) a fourth order zero in the SUSY breaking direction. The potential near the minimum is very steep in the SUSY preserving directions, and very flat in the SUSY breaking direction, consequently the SUSY breaking field has a weak scale mass, while other moduli are heavy. We also argue that there will be additional near by minima with a large negative cosmological constant.