Article View: sci.physics
Article #4600Re: What's a manifold?
From: Bruce Scott
Date: Tue, 10 Nov 1992 18:53
Date: Tue, 10 Nov 1992 18:53
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asimov@nas.nasa.gov (Dan Asimov) writes:
>Yet a third notion is a manifold which happens to be a metric space which
>arose through embedding the manifold in Euclidean space, by measuring the
>distance across the Euclidean space. Interestingly enough, this is not
>very often considered in math research.
>But as *such*, with the extrinsic metric (the one obtained from the
>distance across R^3), your helix will, of course, *not* embed
>"isometrically" in R^2, which I believe is your point.
That was indeed my point, although from the rest of your message, I
had misunderstood what the manifold really was. However, I had thought
that "embedding" really meant in R^n with the appropriate n-dimensional
Cartesian metric: each point described with the corresponding n-tuple.
The thing I really misunderstood seems to have been the theorem. In my
sense of embedding, is there a known minimum N for which *any* 1-D
manifold will extrinsically embed in R^N?
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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Newsgroups: sci.physics,sci.math Path: arc1-ca.pugleaf.net!sparky!uunet!think.com!ames!decwrl!concert!samba!usenet From: Bruce.Scott@launchpad.unc.edu (Bruce Scott) Subject: Re: What's a manifold? Message-ID: <1992Nov10.185338.29742@samba.oit.unc.edu> Sender: usenet@samba.oit.unc.edu Nntp-Posting-Host: lambada.oit.unc.edu Organization: University of North Carolina Extended Bulletin Board Service References: <1992Nov6.190913.18507@nas.nasa.gov> <1992Nov10.000228.14551@samba.oit.unc.edu> <1992Nov10.031324.27265@nas.nasa.gov> Date: Tue, 10 Nov 1992 18:53:38 GMT Lines: 29