This year has been a painful one for fans of the NFL's Indianapolis Colts, the perennial contender that has fallen to 0–10 on the season. Perhaps Hoosiers can take some small comfort in the thought of a world where star quarterback Peyton Manning is healthy rather than hobbled and the Colts are undefeated rather than winless. If the cosmological concept of the multiverse is correct, such a world could exist right now.
Some theoretical explanations for our universe's beginnings imply that big bangs are not rare—in fact, they are happening all the time, producing an infinite array of universes within a larger multiverse. Most universes would be very different from the one we inhabit, but with so many to choose from, some would resemble ours in every respect—or in almost every respect, except that the Colts remain dominant.
In another hypothetical universe Brian Greene is an orchestral conductor, not a theoretical physicist at Columbia University. See for yourself what that corner of the multiverse might look like in the clip below from Greene's NOVA miniseries, The Fabric of the Cosmos. The fourth and final segment of the series details the reasons why many physicists take the multiverse seriously—and why some fear that the idea verges on the supernatural. The episode "Universe or Multiverse?" airs November 23 on PBS.