Domain Walls of D=8 Gauged Supergravities and their D=11 Origin

TL;DR

This paper constructs and analyzes domain wall solutions in eight-dimensional gauged supergravities derived from eleven-dimensional supergravity, revealing their geometric structure and higher-dimensional origins.

Contribution

It introduces a new class of domain wall solutions in D=8 gauged supergravities obtained via Scherk-Schwarz reduction from D=11, including their uplift to eleven dimensions as gravitational instantons.

Findings

Constructed five D=8 gauged supergravities with specific gauge groups.

Derived the most general half-supersymmetric domain wall solutions.

Uplifted solutions to eleven dimensions as gravitational instantons.

Abstract

Performing a Scherk-Schwarz dimensional reduction of D=11 supergravity on a three-dimensional group manifold we construct five D=8 gauged maximal supergravities whose gauge groups are the three-dimensional (non-)compact subgroups of SL(3,R). These cases include the Salam-Sezgin SO(3) gauged supergravity. We construct the most general half-supersymmetric domain wall solutions to these five gauged supergravities. The generic form is a triple domain wall solution whose truncations lead to double and single domain wall solutions. We find that one of the single domain wall solutions has zero potential but nonzero superpotential. Upon uplifting to 11 dimensions each domain wall becomes a purely gravitational 1/2 BPS solution. The corresponding metric has a 7+4 split with a Minkowski 7-metric and a 4-metric that corresponds to a gravitational instanton. These instantons generalize the SO(3) metric of Belinsky, Gibbons, Page and Pope (which includes the Eguchi-Hanson metric) to the other Bianchi types of class A.