- noun the point where the curvature of spacetime is infinite and all the usual rules of physics cease to have effect
- Point where the curvature of spacetime is infinite. Singularities are aptly named – they are the most ‘singular’ and bizarre objects in astronomy, since all the normal rules of physics cease to have effect there. A singularity must lie at the heart of a black hole, surrounded by an event horizon and photon sphere preventing its being observed from the outside universe. At the singularity, matter entering the black hole has no hope of being sustained by its physical strength, even including the forces which hold atoms themselves together. Instead, all material sucked into the hole, including the original matter making up the star which collapsed to make the black hole, is crushed into an infinitely tiny ‘pinhead’ at infinitely high pressure.