Talk detail

Participant	Murata, Keiju
Institution	DAMTP, University of Cambridge - Wilberforce Road - Cambridge - Cambridgeshire - United Kingdom

Session	BH1	Accepted	Yes	Order	2	Time	30'
Talk	Oral abstract	Title	Black hole instabilities and local Penrose inequalities
Co-authors	Pau Figueras, Harvey S. Reall,
Abstract	Various higher-dimensional black holes have been shown to be unstable by studying linearized gravitational perturbations. A simpler method for demonstrating instability is to find initial data that describes a small perturbation of the black hole and violates a Penrose inequality. An easy way to construct initial data is by conformal rescaling of the unperturbed black hole initial data. For a compactified black string, we construct initial data which violates the inequality almost exactly where the Gregory-Laflamme instability appears. We then use the method to confirm the existence of the "ultraspinning" instability of Myers-Perry black holes. Finally we study black rings. We show that "fat" black rings are unstable. We find no evidence of any rotationally symmetric instability of "thin" black rings.