'Einstein’s theory of general relativity states that matter can cataclysmically implode, creating a state where a given density and the space-time curvature split towards infinite values. This is referred to as a singularity, or – as it is known to ordinary folk – a black hole. Extending out from a black hole’s unfathomably dense centre and extraordinary gravitational pull is a finite volume of space that ends in an event horizon: a demarcation – a line in the cosmic sands – from which nothing inside can escape: not rock, metal, Judas Priest, photons, alliteration or anything else. The closer that matter gets to a singularity, the more the laws of physics fail, eventually collapsing entirely.' (Introduction)