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  #51  
Old 12-10-2012, 03:48 PM
md2000 md2000 is offline
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Originally Posted by Learjeff View Post
Ignoring the eyes but just considering two nostrils (that collapse to one passageway, ignoring sinus anomalies), mouth (which collapses to the same passageway along with the nostrils), and anus, that makes us a manifold.

A manifold is something that has one intake and multiple outlets (or vice versa ... or ignore "in and out" but retain the multiple openings to one cavity). That's a different topology from adding pierced ears, which simply adds two new passageways.

So is the characterization of a person with pierced ears a genus-5 manifold incorrect? I would think so.
but 3-in-one-out generally collapses topologically to a donut with 3 donut holes. 5 if we count eustacian tubes. 7 with ear piercings. A manifold is no different than a multi-hole donut - or a set of brass knuckles.

Last edited by md2000; 12-10-2012 at 03:49 PM..
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  #52  
Old 12-10-2012, 03:49 PM
Leo Bloom Leo Bloom is offline
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Then does topology not deal with surfaces (or surface sets) enclosing other surface sets?

Please excuse the grade-school questions.
Wait, so has this been answered and I missed it?
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  #53  
Old 12-10-2012, 04:55 PM
cmyk cmyk is offline
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Quote:
Originally Posted by Leo Bloom View Post
Then does topology not deal with surfaces (or surface sets) enclosing other surface sets?

Please excuse the grade-school questions.
It does, but discrete surfaces (and in the mathematical/geometrical study, usually idealized, abstract ones). So, we really would have to break the body down into as many discrete "objects" as possible. But as an highly complex organism, this is virtually impossible and full of gray areas to take it out of a topological context.

That said, you can sever the eyeball from its nerve, blood supply and muscles, then say, topologically, the surface is a 2-sphere, but the iris inside is a torus.

We all know the skin is full of thousands of pours, the lungs are full a millions of alveoli, and even the circulatory system is a mind-fuck if you go all the way down to the capillary level.

So, saying topologically a human is a torus based on the GI track alone barely cuts it. Where does the GI track begin and end?
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  #54  
Old 12-11-2012, 01:33 PM
Leo Bloom Leo Bloom is offline
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Originally Posted by cmyk View Post
....We all know the skin is full of thousands of pours, the lungs are full a millions of alveoli, and even the circulatory system is a mind-fuck if you go all the way down to the capillary level....
Thanks for the reply.

But I must add that the mind fuck is ameliorated considerably if you must pry white-blood cells off Raquel Welch, or so I've heard.
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