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Topic: the real tube
Replies: 2   Last Post: Feb 15, 2013 8:46 PM

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 Calvin Posts: 351 Registered: 10/27/06
the real tube
Posted: Feb 10, 2013 1:14 AM

Instead of the real line, consider the real tube,
where at each position p along the tube is a disc
of no thickness, at distance p from the zero
disc, and at a right angle to the central line of
the tube. This is not a hollow tube, so each real
number is represented by a disc, not a ring.

Now say that the tube is one centimeter thick
and one meter long, and that it contains the
zero meter disc, 0, but does not contain the one
meter disc, 1.

Now hold up the tube in front of your eye, as you
would hold a telescope, looking toward the zero
meter end. You see the disc 0, face on. Now
turn the tube around and look toward the one
meter end. What do you see?

Date Subject Author
2/10/13 Calvin
2/11/13 Calvin
2/15/13 HH