Witten
It is possible that of the eleven dimensions, the eleventh thanks to Witten's M-theory, the ones we see are the ones that were affected by gravitational inflation and may constitute a brane.
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Notice your use of the words "possible" and "may"
the blog I mentioned from columbia u math dept before has all real math guys there. I pulled a piece out of a longer post of one of these math guys who from first hand experience recounted the history of string theory people from the theory's inception. so i'm inclined to believe the guy when he says that besides the witten stuff "I think string theory has been an utter disaster for theoretical physics"
from what I've read apparently superstring theory fills some kind of philosophical need similiar to that of aether theory in the 19th century.
but if your point is that theoretical physics is showing the darkness that in the past (like in the late 19th century) has generally preceded a pretty big paradigm shift. Then I would agree.
My point is that math is merely useful, but any correlation to reality lies in procurement of project funding.
The covariant derivative is anticommutative.
-willful suspension of disbelief [Coleridge]