In an infinite universe there's a copy of you reading this post - in Latin. The Scientific American updates current cosmological thinking on Parallel Universes - The key question is not whether the multiverse exists but rather how many levels it has - and reaches some startling conclusions.
posted by grahamwell on May 12, 2003 - 40 comments

Parallel universes Alternate universes may exist besides our own in some ghostly manner. Various science-fiction series explore parallel universes, but what do serious physicists think? Hugh Everett III's doctoral thesis outlines a controversial theory in which the universe at every instant branches into countless parallel worlds. Physicist Andrei Linde's theory of self-reproducing universes implies that new universes are being created all the time through a budding process. Stephen Hawking's quantum cosmology also suggests the possibility of other universes connected by wormholes. Some scientists feel that the famous photon double slit experiments proves the existence of parallel universes in which a photon from one universe interacts with a photon from another. Black hole theory suggests that black holes may be portals to parallel universes.
    Science-fiction stories about parallel universes always delight the mind. Two of my favorite SF novels on parallel universes are Heinlein's Job and Number of the Beast. Several others intrigue me, such as The Neoreality Series, Diaspora, and Parallelities. Science books on the subject include a famous book by David Deutsch.
    Do you have any favorite books on parallel universes or parallel realities, fiction or nonfiction? What do you think? No doubt, scientists and science-fiction authors will continue to explore the concept in the decades to come.
posted by Morphic on Oct 21, 2002 - 64 comments