String theory is a quantum theory just like the usual quantum mechanics of a point particle. The need to introduce extra spatial dimensions arises from reasons of mathematical consistency (there are some extra conditions that appear when you quantise a two-dimensional object). But it would be misleading to say that the quantum states of the system are somehow orthogonal to our four-dimensional universe: the extra spatial dimensions are just that, new directions just like length, width and breadth (and notably, not timelike).
It would be nice to see a visualisation of this sort that also gets the facts right. Andrew J. Hanson has created some nice images of three-dimensional cross-sections of Calabi-Yau manifolds, for example.
[Calabi-Yau manifolds are the shape that the extra six dimensions need to have for string theory to yield physically sensible results.]
And of course, everybody knows that M-theory is in fact eleven-dimensional, so Bryanton misses at least one. :-)
- Hannu, recovering string theorist
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|"Main_comments_060806_1" last changed on 06-Aug-2006 20:25:07 EEST by JanneJalkanen.|