manifold embedding
nash proved that any manifold can be embedded in R^3 in which the higher dimensional manifold gets crumpled and smoothness is lost.
is it possible that 11 dimensional space has already crumpled into our three dimensional universe and that wormholes exist precisely as a direct result of the crumpling? cheers, phoenix 
http://www.wikipedia.org/wiki/Nash_embedding_theorem
The theorem says that any Riemann manifold can be (isometrically) embedded in R^{n} for some n. It doesn't say 3 specifically. In fact, n has to be at least as great as the dimension of the manifold. 
there was a big embedding theorem by nash, which is the one you're talking about, and a small embedding theorem, which is the one i'm talking about. it was mentioned in the "a beautiful mind," but i can't find the paper on the web.
cheers, phoenix 
i did a little more research and found this quote from nash's autobiographical essay for winning the nobel:
So as it happened, as soon as I heard in conversation at M.I.T. about the question of the embeddability being open I began to study it. The first break led to a curious result about the embeddability being realizable in surprisingly lowdimensional ambient spaces provided that one would accept that the embedding would have only limited smoothness. And later, with "heavy analysis", the problem was solved in terms of embeddings with a more proper degree of smoothness. so again i ask this: is it possible that the higher dimensional space has either fully or partially collapsed in the three dimensional space and that the nonsmoothness has resulted in wormholes? 
I repeat, no. An ndimensional manifold cannot be embedded in an mdimensional manifold for m < n.

a lot more
actually if you want a lorentzian metric in both manifold, the embedding rises, it needs a lot more of dimensions. About ninety or so, perhaps.

Re: a lot more
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I need to know the Cartan subgroup of SL(2,C) (I am told there is just one and I suspect it is the diagonal matrices but am not sure) 
Re: Re: a lot more
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I am back just on a errand for nuclear data. I am afraid I can not confirm your guess it seems a good one without browsing across manuals :( Two years teaching computer science and you see, one loses the training. 
In the Archive section of this forum I just posted what I think is the Weyl group of SL(2,C). These are new ideas for me, they seem nice
I think the normalizer of the (main) diagonal matrices in SL(2,C) consists of the union of the major and minor diagonal matrices and then N(H)/H the Weyl group comes down to Z_2 which just flips the diagonal matrix to the other directionmajor to minor and viceversa, but there is a minus sign in there too you cant fool me, you have not gotten all that rusty by teaching computer science. it could even give you ideas 
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