Roger Penrose Quotes:
Ocupation: Physicist
Life: b. August 8, 1931
Birthday: August 8
As you say, the way string theory requires all these extra dimensions and this comes from certain consistency requirements about how string should behave and so on.
source: "Secrets of the Old One". "Groks Science" with Frank Ling, grokscience.wordpress.com. January 18, 2009. 
topic: String Theory
