: You said it had artificial gravity, right? I guess since they're so advanced,
: it's some kind of gravity field like they use on ships, but you could also
: walk on the inner surface if it was spinning like a ring.
Except you could only walk on the inner surface along ring intersecting the plane it was spinning on; further away from that ring, the ground under your feet would get steeper and the gravity would get lighter and pretty soon you'd be hanging onto a vertical surface in zero G... at least, zero "artificial G", the pull from the center of gravity on the thing would be pulling you off the wall into the artificial sun in the center of it. While this would allow some place for ships to fly in and out, at the two "hubs", it would essentially make it a big ringworld and no longer a sphere; your habitable area goes way down.
: If it was just lying there, the gravity would just be toward the center,
: right? But that would be inconvenient if you dropped something down there.
Very. Not to mention the above problems...
