There was an old lady who swallowed a fly

摘要

The idea of multiple universes is a surprisingly attractive one. Two deep problems would go away if the universe were not, in fact, universal, but were merely one example of an infinitely large class of such objects. These problems are the true nature of the uncertainty principle, and the "an-thropic principle"-the coincidence that the universe seems to be set up with precisely the right conditions for human-like life to evolve within it. Unfortunately, the sorts of "multiverse" proposed to resolve these two problems are different. The uncertainty principle was developed as part of a way of thinking about quantum theory that is known as the Copenhagen interpretation, because it was orchestrated by Niels Bohr, a Dane. Hei-senberg was one of Bohr's students. But there is an alternative, first proposed in 1957 by Hugh Everett. This is that the universe does actually behave in the deterministic way that 19th-century physicists thought it did; it just looks uncertainly probabilistic. For this to work, however, it cannot be alone. Instead, each event that happens spawns an infinite number of parallel universes, and, taken together, the various versions of the event in question happen with the probability dictated by the uncertainty principle.