From Five Strings To One

Just because you have five different versions doesn't mean you can't bring them together to make one. When you do, you get the "M-theory."

Brian Greene shows how Princeton's Institute for Advance Study's Edward Witten, with the help of others, combined all five string theories successfully. The theory requires the development of 11 dimensions, implying that strings can turn into shapes called membranes, which can also be a universe.  

Join Greene as he explores the possibility of the "M-theory" being just a theory or reality in the last hour of Elegant Universe.

NOVA: Elegant Universe, Pt. 3 airs Wednesday, November 16 at 10 p.m. on WPBT2.