General Relativity (the best gravity theory we have so far):

Relativity: The Special and General Theory - Einstein's 1920 work (translated in English).

Geometry Around Black Holes - with some math.

Relativity on
the World Wide Web - certified by the experts.

The
General Theory of Relativity - lecture by R.Egerton..

The Michelson-Morley Experiment - this is really
related to the Special Relativity, but every non-relativist theory of gravity
must explain it or disprove (or question its results, as this paper by Héctor A. Múnera does).

MOND - really a modification to Newton's laws of motion, but to me (sorry Mr. Milgrom) an example of brute-force curve-fitting

Hypersphere rotation - "Clifford Algebras and Spinors" by Pertti Lounesto.
Use "search inside this book" link to search for "rotating ball" --
you'll get to the chapter "6.6 Rotating ball in R^{4}".

for anti-gravity fans: I'm going to add some links here in the near future - it's just hard to find those that make at least a little sense.

© 2001-2005
Sergey Ivanenko, Redlands, CA