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Topic: Arthur C. Clarke's "The Wall of Darkness" - what's the point?
Replies: 10   Last Post: Apr 2, 2013 3:31 PM

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Brian Q. Hutchings

Posts: 4,962
Registered: 12/6/04
Re: Arthur C. Clarke's "The Wall of Darkness" - what's the point?
Posted: Apr 2, 2013 3:31 PM
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as Bill pointed it out, a Kbottle can be cut into two Mstrips,
but they are really the same thing, if the ideal of "compactness"
is modified. that is, there is a standard way
to parameterize the Mstrip, which arbitrarily limits it
to being a strip, half a unit wide on both sides of the generating
circle.

if it is an infinite surface, it has an irreducible self-intersection,
same as the Kbottle, although this is usually handwaved-away
with some stuff about "4dness."

anyway, you can "do" an Matrip with an old bike tube,
in more than one way. or, maybe it's the Kbottle manifestation.



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