Cosmic Acceleration in Massive Half-Maximal Supergravity

TL;DR

This paper studies how certain supergravity models in higher dimensions can lead to accelerated expansion in lower dimensions, revealing instability in static solutions and supersymmetry breaking.

Contribution

It demonstrates that compactifying massive half-maximal supergravity on a three-sphere results in unstable static solutions and cosmological acceleration.

Findings

Static Minkowski x S^3 configurations are unstable.

Cosmological evolution breaks supersymmetry.

Accelerated expansion occurs in the lower-dimensional spacetime.

Abstract

We consider massive half-maximal supergravity in (d+3) dimensions and compactify it on a symmetric three space. We find that the static configurations of Minkowski X S^3, obtained by balancing the positive scalar potential for the dilaton and the flux of a three-form through the three-sphere, are unstable. The resulting cosmological evolution breaks supersymmetry and leads to an accelerated expansion in d dimensions.