Chard-
I think the point you've missed is that the world wraps around in both non-vertical directions. Not only can you go around the sides, but if you go off the "
round"
edge in the south, you get compressed to a point at the north, and if you somehow go through the point at the north, you are spread out evenly along the edge in the south. I think it's more or less safe to say that the vertical direction extends infinitely upwards. As for downwards, well, that's been a secret (though I think there may be some sort of "
City"
down there, and some kind of Empire
)
WARNING: Crazy math/topology talk ahead
So topologically speaking (it sounds like you've got enough background to understand this), the Eighth is NOT a 3-manifold, nor is its surface a 2-manifold, because of the odd behavior at the north pole. If you removed a closed neighborhood of the north pole, then the surface would be a 2-manifold. Topologically, I think you could, roughly, get the underlying space of the Eighth if you took a closed unit square in 2-space, identified the x and -x sides, identified everything where y = 1 and y = -1 to a point, and then took the product with the real line. But the geometry is a little weird, in that as you approach the "
sqaushed"
point (aka north pole) from the positive y direction, the lateral geodesics shrink down to a length of zero (in particular the length of a lateral geodesic is pi/4 times your distance from the north pole since the angle is pi/4), while if you approach from the negative y direction, the lateral geodesics stay roughly constant. In fact, they grow a little, approaching pi/4 * the distance from the north pole down to the south edge.
Well, I hope someone can understand that. To quote Professor Frink... "
This should be obvious to even the most dim-witted individual... with an advanced degree in hyperbolic topology, mm-hey"
One last thing... It seems to me that it would be impossible for an average denizen of the Eighth to go through the north pole point. If you started walking there, as you got close you would see seven copies of yourself heading to the same point. When you tried to walk through it you would bump shoulders before you could get there. Stick your finger out to the point, and it will bump into seven other fingers. So there's no real way to push past yourself and go through to the other side.
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Yes, I very rarely post. But I DO keep coming back to check the forum.
[Last edited by MartianInvader at 11-17-2006 08:26 PM]