Causal Structure of d=5 Vacua and Axisymmetric Spacetimes

TL;DR

This paper analyzes the causal structure of five-dimensional spacetimes with closed timelike curves, demonstrating that holographic screens and geodesics remain within safe regions, and completes the classification of maximally supersymmetric solutions in minimal five-dimensional supergravity.

Contribution

It extends understanding of CTCs in five-dimensional spacetimes and completes the classification of all maximally supersymmetric solutions in minimal five-dimensional supergravity.

Findings

Bousso's holographic screens are inside the safe region.

Causal geodesics cannot escape the safe region.

Full classification of maximally supersymmetric solutions achieved.

Abstract

We study the structure of closed timelike curves (CTCs) for the near horizon limit of the five dimensional BMPV black hole, in its overrotating regime. We argue that Bousso's holographic screens are inside the chronologically safe region, extending a similar observation of Boyda et al. hep-th/0212087 for Goedel type solutions. We then extend this result to quite generic axisymmetric spacetimes with CTCs, showing that causal geodesics can't escape the chronologically safe region. As a spin-off of our results, we fill a gap in the identification of all maximally supersymmetric solutions of minimal five dimensional supergravity, bringing this problem to a full conclusion.