N=4 "Fake" Supergravity

TL;DR

This paper extends the concept of fake supergravity to 5D, N=4 gauged supergravity, analyzing BPS-domain walls and revealing conditions under which they can be curved or flat, with implications for universal behaviors in such theories.

Contribution

It generalizes fake supergravity to N=4 supergravity and identifies constraints on the curvature of BPS-domain walls based on gauge groups and scalar support.

Findings

Curved BPS-domain walls cannot be supported solely by scalars in N=4 supergravity.

Purely Abelian or semisimple gauge groups cannot produce curved domain walls.

Flat walls with these gaugings show runaway behavior.

Abstract

We study curved and flat BPS-domain walls in 5D, N=4 gauged supergravity and show that their effective dynamics along the flow is described by a generalized form of "fake supergravity". This generalizes previous work in N=2 supergravity and might hint towards a universal behavior of gauged supergravity theories in supersymmetric domain wall backgrounds. We show that BPS-domain walls in 5D, N=4 supergravity can never be curved if they are supported by the supergravity scalar only. Furthermore, a purely Abelian gauge group or a purely semisimple gauge group can never lead to a curved domain wall, and the flat walls for these gaugings always exhibit a runaway behavior.