Gravity is a force, which depends from a masses of objects. And there is a gravity between an Earth and Sun.
Let's assume that there is a momental loss of the mass in the Sun, in a considerable amount of the mass of the Sun. And the question is: how much time is needed for this change of gravity, if the loss of the mass is momental and distance between Earth and Sun is 8 light minutes.

According to the theory of general relativity, changes in the gravitational field propagate at the speed of light. Hence, if the sun disappeared now, the Earth would not know anything about it, either by light or gravity, for another 8 minutes.

Proof of this is that the earth orbits around the point where the sun 'appears' to be, rather than where it actually is.

At last there may be a decent experiment testing the speed of light, though we have to wiat till January the 11th for the results.

Experiment (http://hometown.aol.com/MetPhys/129gravtest.html)

Duncan

My bet is on the speed of light.

Remember that gravity is a probability field.

Even if there were something like the higg boson to exchange information (from particles to the field, and limited but the speed of light), there still remains the hint that actions over distance faster than the speed of light is possible...

Like as in the EPR experiment: perhaps all points of space/time are actually the same point!

Probability is not governed by the speed of light , and `information` is lost due to the uncertainty principle.

So, IMHO, inertia (mass and gravity) is actually dependant on the location of all points (near and far) at the same time...