He and I went to the same school but not together. I was quite a few years ahead of him.
I did read his book and I thought i had it here but cannot find it right now.
I admit that he tends to describe everything in a catastrophic way, in order to sell more of his books. But actually he is just talking about standard superstring theory. For a more balanced rendtion of the same subject read Brian Greene's "the Elegant Universe" or watch his Nova series on string theory starting this week.
Here is the problem. From superstring theory we know that matter can only be made in 10 or 11 dimensions. So what happens to the extra 6 or 7 dimensions. It is hypothesized that they somehow curl up into Planck size balls or cylinders. The problem is that there are a million ways they could roll up, and no one knows how it happens. Not even Micchio, who is not really a researcher in the field. He is just speculating. He does not have a theory.
As an aside, the first ever description of how the extra dimensions rolled up was in the Kabala book called "The Book of Creation" supposedly written by Abraham, and first published about a 1000 years ago. Nobody has presented a better description yet, not Brian and not Micchio.
So calling it a catastrophe is clearly the work of a huckster.
The latest good work is being done is in Loop Quantum Gravity rather than string theory. LQG is a theory that can derive 4-d spacetime from loops, whatever they are, and can derive the big bang. As far as I know 'matter' has not been derived yet unless it comes out of the big bang papers. The leading light in this field is Smolin who was in Harvard with Kaku, but Smolin does real research, whereas Kaku is a radio showman.
I have referenced the latest LQG papers in this forum. See threads below that no one responds to.
Of course, I have no right to diss Micchio as I never did real research in high energy physics. I did all my research on Star Wars. But take it from me, his catastrophe is a figment of his imagination.