Brane-world Kaluza-Klein reductions and Branes on the Brane

TL;DR

This paper introduces a new class of consistent brane-world Kaluza-Klein reductions in gauged supergravity, providing explicit solutions and analyzing singularities at the Cauchy horizon, with implications for string and M-theory compactifications.

Contribution

It systematically develops a novel type of brane-world Kaluza-Klein reduction and explores its higher-dimensional origins and explicit brane solutions.

Findings

Explicit solutions of brane configurations on the world-brane.

Identification of curvature singularities at the Cauchy horizon.

Massive Kaluza-Klein modes do not regulate these singularities.

Abstract

We present a systematic study of a new type of consistent ``Brane-world Kaluza-Klein Reduction,'' which describe fully non-linear deformations of co-dimension one objects that arise as solutions of a large class of gauged supergravity theories in diverse dimensions, and whose world-volume theories are described by ungauged supergravities with one half of the original supersymmetry. In addition, we provide oxidations of these Ansatze which are in general related to sphere compactified higher dimensional string theory or M-theory. Within each class we also provide explicit solutions of brane configurations localised on the world-brane. We show that at the Cauchy horizon (in the transverse dimension of the consistently Kaluza-Klein reduced world-brane) there is a curvature singularity for any configuration with a non-null Riemann curvature or a non-vanishing Ricci scalar that lives in the world-brane. Since the massive Kaluza-Klein modes can be consistently decoupled, they cannot participate in regulating these singularities.