Supersymmetric Vacuum Configurations in String Cosmology

TL;DR

This paper explores conditions for unbroken supersymmetry in string cosmology, finding solutions that interpolate between Minkowski and DeSitter spaces with potential implications for non-singular pre-big-bang models.

Contribution

It demonstrates how a non-vanishing gravitino-dilatino condensate can lead to supersymmetric, non-singular cosmological solutions in string theory.

Findings

Identifies conditions for unbroken supersymmetry in D=10 supergravity.

Constructs a solution interpolating between Minkowski and DeSitter space.

Proposes a supersymmetric, non-singular pre-big-bang cosmology.

Abstract

We examine in a cosmological context the conditions for unbroken supersymmetry in N=1 supergravity in D=10 dimensions. We show that the cosmological solutions of the equations of motion obtained considering only the bosonic sector correspond to vacuum states with spontaneous supersymmetry breaking. With a non vanishing gravitino-dilatino condensate we find a solution of the equations of motion that satisfies necessary conditions for unbroken supersymmetry and that smoothly interpolates between Minkowski space and DeSitter space with a linearly growing dilaton, thus providing a possible example of a supersymmetric and non-singular pre-big-bang cosmology.