Holographic duality (also called gauge/gravity duality or the AdS/CFT correspondence) relates a string theory — i.e. a quantum theory of gravity — to a quantum field theory without gravity. Currently it is an area of research located at the confluence of previously seemingly distant fields in physics and mathematics including superconductivity and other exotic phases of strongly coupled quantum matter, string theory, numerical general relativity and the theory of non-linear partial differential equations. The main aim of the programme is to bring together experts in these diverse fields to...