🚀 go-pugleaf

In article <CMM.0.90.2.713030681.alsberg@delphi.uio.no> Bj|rn Alsberg writes:
> [ presumably in a list of "interesting problems" ]
> - Simulations of the gravitational field of an Earth sized torus. 
> What are the effects on the atmosphere and the sea level at different 
> locations at the surface.

In article <1992Aug7.071512.1046@nntp.hut.fi> jtyrkko@vipunen.hut.fi
(Juha-Petri Tyrkk|) writes:
>  Has anybody calculated this or does anybody have a ready-made
>answer? My intuitive guess would be that inside the hole of the torus
>the gravity would be so weak that any gaseous atmosphere would escape
>into space. On a planet much greater than Earth things might differ.

Here are references to several science fiction novels treating this
and other "wierd gravity planet" scenarios:

	Hal Clement
	"Mission of Gravity"
	Doubleday, Garden City, 1954
	no ISBN
		[This is a nice book, with a really beautiful
		evocation of the ethos of the scientific method
		in the ending.]

	Hal Clement
	"Still River"
	Ballentine, New York, 1987
	ISBN 0-345-32917-1

	"Bulge"
	chapter in
	Lester Del Ray, Editor
	"The Best of Hal Clement"
	Ballentine, New York, 1979
	ISBN 0-345-27689-2

		[Note "Hal Clement" is actually a high school
		 physics teacher.  There's a brief biography of
		 him in the back of the last of these books, but
		 I guessed his occupation within 50 pages of the
		 first, and so would anyone else with a physics
		 background.]

	Boyd, John Philip
	"The Moonbow"
	Isaac Asimov's SF Mag 5 [1981], 18-37
	[properties of a toroidal world]

	Boyd, John Philip
	"Earthflight"
	chapter (pages 201-218) in
	S. Shwarz, Editor,
	"Habitats",
	DAW [???], New York, 1984.
	[also about a toroidal planet]

		[Both of these are from the bibliography in
		Boyd's *beautiful* book "Chebyshev and Fourier
		Spectral Methods".  The preface mentions that
		he's the author of *14* SF and mystery short
		stories.  I have no information about the others.]

- Jonathan Thornburg
  <jonathan@einstein.ph.utexas.edu> or <jonathan@hermes.chpc.utexas.edu>
  University of Texas at Austin / Physics Dept / Center for Relativity
  and (for a few more months) U of British Columbia / {Astronomy,Physics}