The Goldstino Brane, the Constrained Superfields and Matter in N=1 Supergravity

TL;DR

This paper compares different formulations of the goldstino in N=1 supergravity, highlighting the geometric brane approach's advantages in off-shell supersymmetry and explicit nilpotent superfield solutions, with applications to matter couplings and string compactifications.

Contribution

It demonstrates the equivalence of brane and constrained superfield descriptions and details the geometric goldstino brane approach's benefits in supergravity models.

Findings

The geometric goldstino brane approach is off-shell supersymmetric without auxiliary fields.

Explicit solutions for nilpotent superfield constraints are provided.

Applications include goldstino contributions to gravitino mass and string compactifications.

Abstract

We show that different (brane and constrained superfield) descriptions for the Volkov-Akulov goldstino coupled to N=1, D=4 supergravity with matter produce similar wide classes of models with spontaneously broken local supersymmetry and discuss the relation between the different formulations. As with the formulations with irreducible constrained superfields, the geometric goldstino brane approach has the advantage of being manifestly off-shell supersymmetric without the need to introduce auxiliary fields. It provides an explicit solution of the nilpotent superfield constraints and avoids issues with non-Gaussian integration of auxiliary fields. We describe general couplings of the supersymmetry breaking sector, including the goldstino and other non-supersymmetric matter, to supergravity and matter supermultiplets. Among various examples, we discuss a goldstino brane contribution to the gravitino mass term and the supersymmetrization of the anti-D3-brane contribution to the effective theory of type IIB warped flux compactifications.