The Topology of Space Outside Black Holes
Martin LeSourd (Mathematics) – BHI
Title: The Topology of Space outside Black Holes
Abstract: It has long been known (mid 90s) that assuming certain topological properties about a spacetime’s future conformal boundary, along with various other reasonable assumptions, forces the region outside a black hole to be topologically trivial. This result and the ones that have come after are known as “topological censorship”. In light of those theorems, we asked ourselves the following: i) what happens if we introduce a positive cosmological constant term (as observations suggest), and ii) can we get rid of assumptions about the topology of the future conformal boundary? I shall describe the answers we found to those questions. The work is joint with E.Ling.
Bio: Martin Lesourd completed his undergraduate and graduate studies in Mathematics, Physics and Philosophy at (Trinity) Cambridge University and (Linacre) Oxford University. He is a mathematician whose research lies in two disciplines: general relativity and geometric analysis. Broadly speaking, his aim is to better understand a space – this could be a spacetime (which contains a black hole for instance) or a Riemannian Manifold – by studying Partial Differential Equations that can be associated to that space. With regards to general relativity, he studies both the Einstein equations and the Constraint equations, and most recently has been trying to describe the formation of black holes from a purely mathematical standpoint.
