The Ekpyrotic Theory

The Ekpyrotic Universe is simply the Big Bang Theory, with some slight variations.  It tries to explain the beginning of the Big Bang, as many feel the beginning does not make much sense.  What sparked the Big Bang?  Why did the 'cosmic egg' explode?  Well, in the Ekpyrotic Universe, instead of starting as a superheated egg, the Universe begins as cold and empty and vacuous.  Supposedly, the Universe we know came from a gigantic collision between different dimensions.  The Ekpyrotic theory article attempted to explain how these dimensions collided and expanded into today's Universe, but did not succeed too well.  I'd say the biggest flaw in the theory was that i couldn't even understand it!  I read the article several times over, and still barely managed to grasp the concept of the overlapping dimensions.  Also, what caused these dimensions to overlap in the first place?  The next biggest flaw, of course, is that no one was there to witness the birth of the Ekpyrotic Universe.