Violating weak cosmic censorship in AdS$_4$

Abstract: We consider time-dependent solutions of the Einstein-Maxwell equations using anti-de Sitter (AdS) boundary conditions, and provide the first counterexample to the weak cosmic censorship conjecture in four spacetime dimensions. Our counterexample is entirely formulated in the Poincar\'e patch of AdS. We claim that our results have important consequences for quantum gravity, most notably to the weak gravity conjecture.