End Point of Black Ring Instabilities and the Weak Cosmic Censorship Conjecture

TL;DR

This paper provides numerical evidence that in five-dimensional asymptotically flat spacetimes, black rings can violate the weak cosmic censorship conjecture through instabilities leading to horizon pinch-offs.

Contribution

First numerical demonstration showing black ring instabilities can lead to violations of the weak cosmic censorship conjecture in five dimensions.

Findings

Thin black rings exhibit Gregory-Laflamme instability leading to horizon pinch-off.

Slightly thicker rings tend to settle into spherical black holes.

Different instability modes dominate depending on the ring's thickness.

Abstract

We produce the first concrete evidence that violation of the weak cosmic censorship conjecture can occur in asymptotically flat spaces of five dimensions by numerically evolving perturbed black rings. For certain thin rings, we identify a new, elastic-type instability dominating the evolution, causing the system to settle to a spherical black hole. However, for sufficiently thin rings the Gregory-Laflamme mode is dominant, and the instability unfolds similarly to that of black strings, where the horizon develops a structure of bulges connected by necks which become ever thinner over time.