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Posted by Carmen J. Nappo on 07/04/2016
I've just finished EON. Very imaginative work. However, imagination and reality often do not mix. For example, centrifugal force is not similar to gravitational force. The two forces are similar in effect when a mass is in contact with a rotating structure, i.e. the Stone. However; if I were on the Stone's wall and jumped upward, I would not fall back to the wall. Instead, I would continue moving upward. Because of this, an atmosphere could not exist inside the Stone. Of course, coming some some 20 years after the publication of EON, my comments are somewhat moot. Still, I think that in science fiction the known science should be true. For example, it is not critical what the value of Plank's constant is, as long as there is a Plank's constant. But all-in-all, it's a great read.
Posted by Bill Goodwin on 07/23/2016
Sorry to nit-pick, but you would indeed "fall" back to the wall of a rotating habitat after jumping upward (or toward the axis). When your feet leave the inner surface, you retain the momentum you had at that moment, which was directed tangentially in the spin-ward direction. Add the upward motion of your jump and you're in a slantwise trajectory...but remember that the surface "underneath" you keeps rotating while you're in the air. If the habitat is big enough, your jumping-off point will be right there to meet you when that trajectory brings your feet back into contact with the outer shell. At smaller sizes walking and jumping become difficult, but you don't lose the centrifugal effect, and the atmosphere is fine. If you want to float away toward the axis, your best bet is to run very fast in the anti-spinward direction. THAT will cancel out the gravity, and you'll be on your own.
Posted by A Culture Mind on 01/05/2017
Yeah, didn't you ever spin marbles in a bucket or bowl - and then 'jump' them a little, wherein they return to their trajectory around the inside of the container - unless your force exceeded the acceleration inside, wherein like Bill says they'd escape. But one g rotation is a LOT to exceed. It's called escape velocity, yo.
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