Larry Niven has written an essay on Dyson spheres, Ringworlds, etc.,
called "Bigger Than Worlds". As of a few years ago, this essay could
be found in the book _A_Hole_In_Space_. I don't know if it is still
in print.
The New Number Who, oka...@ucbvax.berkeley.edu
Jeff Okamoto ..!ucbvax!okamoto