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Article #4500

Re: What's a manifold?

#4500
From: Bruce Scott
Date: Tue, 10 Nov 1992 00:02
27 lines
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asimov@wk223.nas.nasa.gov (Daniel A. Asimov) writes:

>As has been mentioned, it *is* a theorem that all manifolds do occur
>as subspaces of some Euclidean space: in fact, any n-manifold embeds in R^(2n).
>
>This is a pleasant theorem, but it would be inappropriate to take this as a 
>definition.

What about the one-dimensional helix embedded in R^3. Is the helix not a
1-manifold? Note that if you compact it along its axis you get a circle
(also a 1-manifold--is this S^1?) embedded in R^2. But a circle is a
degenerate case of a helix ("stretching" along the axis having vanished)
and is not in general a helix.

Someone educate me on this.

Gruss,
Dr Bruce Scott                             The deadliest bullshit is
Max-Planck-Institut fuer Plasmaphysik       odorless and transparent
bds at spl6n1.aug.ipp-garching.mpg.de                 -- W Gibson


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From: Bruce.Scott@launchpad.unc.edu (Bruce Scott)
Subject: Re: What's a manifold?
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References: <SMITH.92Nov5132141@gramian.harvard.edu> <1992Nov6.024142.6758@galois.mit.edu> <1992Nov6.190913.18507@nas.nasa.gov>
Date: Tue, 10 Nov 1992 00:02:28 GMT
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