Talk:Topopolis

Rotational Difficulties
How would a tube in a circle or torus knot rotate around its axis (the inner axis of the tube, required to keep artificial gravity) unless it were flexible or segmented? Such a structure would have vast stresses on it...I'm no engineer, but I think that would rule out flexibility. So is it segmented then? -Fëaluinix 10:27, 12 January 2007 (UTC)

Actually, the stresses are rather small. The radius of Earth's orbit is 1.5e8 m; if a topopolis is 3 km in diameter then the proportional change in the length of the tube as it rotates is 2e-5. As it turns out, changes in temperature cause a proportional change in the length of steel of 2e-5 per degree C, so the stress due to rotation is roughly the same as that due to a temperature change of 1 degree. 70.130.202.121 11:35, 4 May 2007 (UTC)