A classification of possible civilizations after energy usage. Type I civilizations control all available energy on a single planet. Type II civilizations control all available energy in a solar system (for example, using Dyson spheres). Type III civilizations control use all available energy in an entire galaxy. (Mitch Porter suggested that a Type IV civilization controls all available energy in the entire universe) We are currently moving towards a Type I civilization. Join discussion...

A small artificially created universe linked to the old universe by a wormhole. This could then be used for living space, computing or as an escape from a decaying universe. "Baby Universes" has been postulated by some theories about black holes and inflation cosmology. Join discussion...