BBC Parallel Universes

http://www.bbc.co.uk/science/horizon/2001/parallelunitrans.shtml

NARRATOR (DILLY BARLOW): Imagine you could find an explanation for everything in the Universe, from the smallest events possible to the biggest. This is the dream which has captivated the most brilliant scientists since Einstein. Now they think they may have found it. The theory is breathtaking and it has an extraordinary conclusion: that the Universe we live in is not the only one.

MICHIO KAKU (City University of New York): That there could be an infinite number of universes each with a different law of physics. Our Universe could be just one bubble floating in an ocean of other bubbles.

NARRATOR: Everything you are about to hear is true, at least in this Universe it is. For almost a hundred years science has been haunted by a dark secret: that there might be mysterious hidden worlds beyond our human senses. Mystics had long claimed there were such places. They were, they said, full of ghosts and spirits. The last thing science wanted was to be associated with such superstition, but ever since the 1920s physicists have been trying to make sense of an uncomfortable discovery. When they tried to pinpoint the exact location of atomic particles like electrons they found it was utterly impossible. They had no single location.

ALAN GUTH (Massachusetts Institute of Technology): When one studies the properties of atoms one found that the reality is far stranger than anybody would have invented in the form of fiction. Particles really do have the possibility of, in some sense, being in more than one place at one time.

NARRATOR: The only explanation which anyone could come up with is that the particles don't just exist in our Universe. They flit into existence in other universes, too and there are an infinite number of these parallel universes, all of them slightly different. In effect, there's a parallel universe in which Napoleon won the Battle of Waterloo. In another the British Empire held on to its American colony. In one you were never born.

ALAN GUTH: Essentially anything that can happen does happen in one of the alternatives which means that superimposed on top of the Universe that we know of is an alternative universe where Al Gore is President and Elvis Presley is still alive.

NARRATOR: This idea was so uncomfortable that for decades scientists dismissed it, but in time parallel universes would make a spectacular comeback. This time they'd be different, they'd be even stranger than Elvis being alive. There's an old proverb that says: be careful what you wish for in case your wish comes true. The most fervent wish of physics has long been that it could find a single elegant theory which would sum up everything in our Universe. It was this dream which would lead unwittingly to the rediscovery of parallel universes. It's a dream which has driven the work of almost every physicist.

MICHIO KAKU: On the ice rink I am communing with the fundamental laws of physics. At the instant of creation we believe that the Universe was symmetrical, it was pure, it was elegant. Without friction Newtonian laws are laid bare, simple, elegant and beautiful, pure, noble, elemental, just like it was at the beginning of time. When I was a child of eight my elementary school teacher came in the room and announced that a great scientist had just died and on the evening news that night everyone was flashing pictures of his desk with the unfinished manuscript of his greatest work. I wanted to know what was in that manuscript. Years later I found out that it was the attempt of Albert Einstein to create a Theory of Everything, a theory of the Universe and I wanted to be part of that quest.