Abstract

It has been known for some time that the black hole uniqueness theorem does not extend to higher dimensional spacetimes. I will argue that the classification of five dimensional asymptotically flat black hole solutions is far from complete, even for solutions with the same symmetry as the known spherical black holes and black rings. The reason for this stems from the possibility that the exterior region may have non-trivial topology (2-cycles). I will illustrate this by presenting two novel supersymmetric black hole solutions to five dimensional supergravity. The first is a black hole with a horizon of lens space topology: a black lens. The second is a spherical black hole with a 2-cycle in the exterior region. The latter solution may carry the same conserved charges as the known spherical black hole (BMPV), thereby demonstrating black hole non-uniqueness even amongst spherical black holes.