A group of physicists
are gathering evidence that we exist in parallel universes (and are part of a multiverse); not a new
concept but interesting that the concept has not "died" but
continues to be studied. The theory of parallel universes actually started after the discovery of quantum mechanics.
This concept was actually devised in 1954 by a young Princeton University doctoral candidate named Hugh Everett III. His idea was that parallel universes exist, exactly like our universe. Each of these universes are related to ours. In fact, they branch off from ours, and our universe is branched off of others.
Everett proposed that within these parallel universes, the wars that we had on our Earth had different outcomes. Species that are extinct in our universe have evolved and adapted in others. In other universes, we humans may have become extinct.
In the 1960s, DC Comics caught onto that idea and put it into comic book lore. In the 1940s there was a character named "The Flash" who wore a helmet like Mercury, the Roman God of speed. In the 1960s a redesigned Flash was created on a "different Earth" and eventually the two Flashes of parallel universes (and Earths) met - as seen in this famous cover of the Flash comic book. So, open your mind and take a look at this video put together by "Minute Physics" about parallel worlds. You may come away with a new understanding. Oh, and pick up a copy of Flash comics. :)
VIDEO: http://youtu.be/Ywn2Lz5zmYg
Minute Physics provides an energetic and entertaining view of old and new problems in physics -- all in a minute!
Music by Nathaniel Schroeder http://www.soundcloud.com/drschroeder
Drums by Jason Burger http://masonjarmusic.com