Ghost-Free de Sitter Supergravities as Consistent Reductions of String and M-theory

TL;DR

This paper explores ghost-free supergravity theories with non-compact gaugings, their higher-dimensional origins via consistent reductions, and investigates de Sitter vacua, black holes, and cosmological solutions.

Contribution

It demonstrates the existence of ghost-free supergravities with non-compact gaugings derived from consistent reductions on hyperboloidal spaces, including explicit examples and solutions.

Findings

Supergravities with non-compact gaugings are ghost-free.

Explicit consistent reductions on hyperboloidal spaces are constructed.

De Sitter vacua and solutions like black holes are identified.

Abstract

We study properties of supergravity theories with non-compact gaugings, and their higher-dimensional interpretations via consistent reductions on the inhomogeneous non-compact hyperboloidal spaces {\cal H}^{p,q}. The gauged supergravities are free of ghosts, despite the non-compactness of the gauge groups. We give a general discussion of the existence of stationary points in the scalar potentials of such supergravities. These are of interest since they can be associated with de Sitter vacuum configurations. We give explicit results for consistent reductions on {\cal H}^{p,q} in various examples, derived from analytic continuation of previously-known consistent sphere reductions. In addition we also consider black hole and cosmological solutions, for specific examples of non-compact gaugings in D=4,5,7.