Might we suddenly be annihilated by a parallel universe? A NewScientist.com story answers with a definitive maybe. The theory that this might be possible comes from the fashionable many-worlds" interpretation of quantum mechanics, which posits the constant creation of a near-infinite number of universes. Many-worlds adherents have heretofore always specified that these universes are completely separate—that is, there is no way one could communicate with another. But a new theory, created to make the many-worlds interpretation fit the data of our existence, suggests that these universes might indeed interact in a meaningful way. And when you have interaction, you have the potential for problems. Like the complete destruction of everything in existence.
A few caveats: The many-worlds interpretation isn't really orthodox in the scientific community. I personally feel its nonsense—any solution that requires the constant creation of entire new universes to explain away our ignorance of fundamental quantum processes is really no solution at all. In addition, the gentleman who came up with the latest many-worlds-interacting theory is an economist, not a physicist. Earning a Ph.D. doesnt make you an expert in everything.
[For a slightly lighter take on annihilation, check out Sam Hughes hilarious and disurbingly thorough Geocide site.] —Michael Moyer