At 12:46 PM 2/15/99 -0600, Natasha wrote:
>I need an explanation from someone(s) on the lists of superstring theory;
>why 11 dimensions rather than 12, and also membrane theory.
Take a look at the tale as told by one of the founders, Prof. John H. Schwarz, California Institute of Technology
http://theory.caltech.edu/people/jhs/strings/index.htm
Superstrings looked good in 10 dimensions, but some calculations were intractably difficult. Lately, Ed Witten's M-theory showed an additional symmetry, duality, which yields nonperturbative solutions previously inaccessible. Because this version is formulated in 11 dimensions, it allows fundamental or elementary membranes or sheets rather than just strings. More recently still, F-theory proposes a yet-higher unification in 12-dimensions. Check the web. Of course the real action is heinously obscure.
Damien Broderick