Kugelblitz (astrophysics) From Wikipedia, the free encyclopedia For other uses, see Kugelblitz (disambiguation). In theoretical physics, a kugelblitz (German: "ball lightning", not to be confused with ball lightning) is a concentration of light so intense that it forms an event horizon and becomes self-trapped: according to general relativity, if enough radiation is aimed into a region, the concentration of energy can warp spacetime enough for the region to become a black hole (although this would be a black hole whose original mass-energy had been in the form of radiant energy rather than matter). In simpler terms, a kugelblitz is a black hole formed from energy as opposed to mass. According to Einstein's general theory of relativity, once an event horizon has formed, the type of mass-energy that created it no longer matters. A kugelblitz is so hot it surpasses the Planck temperature, the temperature of the universe 5.4×10−44 seconds after The Big Bang. The best-known reference to the kugelblitz idea in English is probably John Archibald Wheeler's 1955 paper "Geons",[1] which explored the idea of creating particles (or toy models of particles) from spacetime curvature. Wheeler's paper on geons also introduced the idea that lines of electric charge trapped in a wormhole throat might be used to model the properties of a charged particle-pair. A kugelblitz is an important plot element in Frederik Pohl's novel Heechee Rendezvous.