The Edge Of Supersymmetry: Stability Walls in Heterotic Theory

TL;DR

This paper investigates how changing moduli in heterotic Calabi-Yau compactifications affect supersymmetry, revealing the emergence of an anomalous U(1) gauge symmetry at the boundary of supersymmetric regions and its role in gauge bundle stability.

Contribution

It explicitly describes the behavior of heterotic compactifications at the edge of supersymmetry preservation using four-dimensional N=1 supersymmetric field theory.

Findings

Anomalous U(1) gauge symmetry appears at the supersymmetry boundary.

D-term contributions enforce gauge bundle stability.

Provides a low-energy effective description of supersymmetry breaking boundaries.

Abstract

We explicitly describe, in the language of four-dimensional N=1 supersymmetric field theory, what happens when the moduli of a heterotic Calabi-Yau compactification change so as to make the internal non-Abelian gauge fields non-supersymmetric. At the edge of the region in Kahler moduli space where supersymmetry can be preserved, an additional anomalous U(1) gauge symmetry appears in the four-dimensional theory. The D-term contribution to the scalar potential associated to this U(1) attempts to force the system back into a supersymmetric configuration and provides a consistent low-energy description of gauge bundle stability.