Question about gravity propagation in GR and string theory

This is my first post here, so bear with me!I have a question about how exactly gravity propagates, both in GR and in superstring theory. In trying to investigate this question, I am encountering conflicting information and am left somewhat confused.In this page it seems to suggest that experiment tells us that the "speed" of gravity seems be much faster than light. The conclusion there is:Conclusion: The speed of gravity is 2x10^10 cHowever, when I read this page I see:In general relativity, on the other hand, gravity propagates at the speed of light; that is, the motion of a massive object creates a distortion in the curvature of spacetime that moves outward at light speed.Or in this article a researcher states, "Our main goal was to rule out an infinite speed for gravity, and we did even better. We now know that the speed of gravity is probably equal to the speed of light, and we can confidently exclude any speed for gravity that is over twice that of light"What is the currently accepted answer to this, or is it "We aren't sure" at this point?Now when it comes to superstring theory (of which I also understand little), the graviton is one of the predicted particles yielded by string resonance. If gravity is transmitted by the graviton, is that not subject to the light speed limit? Does string theory contradict GR anyway and claim that mass does not warp space-time, or in other ways?Thanks in advance everyone!This message has been edited by BuckeyeChris, 07-20-2005 02:40 AM

Thread moved here from the Proposed New Topics forum.

The first link that you supplied is part of a larger web site. This web site seems to be a "crank" site -- one article they have is "proof" that the face on Mars is artificial.I did look at the link in question, but I don't know enough about GR to tell how much of his claims are true; however, given the nature of his site I wouldn't trust any of it. Perhaps those who know more about cosmology and GR can give a better expert analysis.

We pretty much know that it moves at the speed of light.However since speed involves moving in spacetime and gravity is the warping of spacetime, it doesn't really move in any proper sense of the word.
Its speed is calculated from the point of view of a flat space observer.
(There are many terms for this observer, such as the coordinate observer, Minkowski observer, e.t.c.)
However since spacetime near Earth is nearly flat, we can pretty much measure it.

That first link is standard crank stuff. You can spot it a mile off by their simultaneous use of Newtonian and GR concepts. It reveals a major lack of real understanding of GR. Talk of GR in one breath and "force" and "acceleration" in another is very undergrad. To see how space-time responds to dynamical changes, you just need to examine an exact dynamical metric, such as the C-metric which describes two accelerating black holes. No, not at all. String theory just provides the "mass" as a consistent part of the theory, where as in GR it is artificially inserted. This is a substantial improvement over GR.

Ah thanks for pointing that out Chiro, I didn't look at the larger site it was a part of. That definitely clears up a source of my confusion.