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General relativity from A to B Robert Geroch
Publisher: U.Chicago

This handsome image of Einstein himself came from art.com. Gravity Probe B Proves General Relativity Still Valid. One of the most spectacular and successful ideas of the 20 Century was Einstein's General Relativity, or the idea that matter and energy determines the curvature of spacetime, and the curvature of spacetime in turn determines how gravitation works. Well, I went to my office that night to do a bit of archeology. Gravity Probe - B Instrument and Data Reduction. Visualization of Einstein's special relativity - YouTube A visual demonstration of the effects of Einstein's relativity. The Gravity Probe-B measured the geodetic effect, the amount that Earth warps the space and time in which it sits, and frame-dragging, or the extent that Earth's rotation churns spacetime around with it. (“Gravity: An Introduction to Einstein's General Relativity”, James B. A gravity probe whose origins date to the era before human spaceflight has finally proved general relativity right, according to NASA. Has finally proved general relativity right, according to NASA. A few “test your understanding” questions: In what year did Albert Einstein develop and publish his Theory of General Relativity? The GP-B satellite was launched in April 2004 and collected a year's worth of data to determine if predictions of Albert Einstein's General Theory of Relativity are correct. In particular, white dwarfs — like Sirius B, illustrated above — condense a Sun's worth of mass into a volume of only the Earth, creating spacetime that's curved 100 times more severely than at our Sun's photosphere. That's definitely true for physicists because the best interpretation of General Relativity supports B-Theory (though I've seen any physicist talk in terms of “A” or “B” Theory of Time). Lecture notes closeup Among the things that have stayed the same? Gravity Probe - B and General Relativity. The rotation of the Earth affects the movement of spacetime itself. Of course general relativity is really about semi-Riemannian geometry [though physicists like to refer to it as merely 'Riemannian'], so you would want to also refer to texts like O'Neill's Semi-Riemannian Geometry With Applications to Relativity. "General Relativity from A to B" explained to me the meaning of the radar-coordinates (emphasizing operational measurements) and the meaning of the spacetime interval (emphasizing the causal structure).