Our buddies over at PopSci have just put up a surprisingly accessible video (given its subject matter) that uses Super Mario to explain the multiverse. Click on the above and you'll find a fairly succinct explanation of the many-worlds hypothesis, as illustrated by a modified version of that classic Nintendo game. For something a little more in-depth, you can check out our 50th anniversary (of the many-worlds hypothesis) feature package that appeared in December of last year (subscribers only), or last november's feature on new evidence for the multiple-worlds hypothesis (free!) As Abby Seiff, the author of PopSci's article on the subject, puts it: You're unique. Aren't you? One of the more creative hypotheses surrounding quantum mechanics posits the exact opposite. Though we can readily see only one world, quantum mechanics says that when we're not observing the particles that make up that world, those particles exist in multiple places at once.... In this John Pavlus edit of a postsilence video, the 134 overlaid playthroughs represent the manifold possibilities Mario encounters as he progresses through his world. Pavlus also plies his trade for us -- you can check out his video handiwork on our channel of sciam video exclusives. -- Edited by christopher.mims at 03/21/2008 1:22 PM