
A Google user
Nine types of parallel universes are proposed including quilted, inflationary, brane, cyclic, landscape, quantum, holographic, simulated and ultimate. The questions include how to test these theories, e.g. involving features which are common, or correlated, to the known universe, possibly through computation, and whether they can be used to solve problems. Various components such as black holes, string theory, and branes are explored and related to each model. There are eleven chapters.