Gravity Goes Faster Than Light?

[Mazerakham]

I would have added this post to the other thread on Gravity, but I thought this was too theoretical of a segway, so it needed its own thread.

But, if gravity fields transmit instantaneously, then wouldn't it be a way of transmitting information faster than light? (Say, a sort of gravity Morse Code if you will).

If we had sensitive enough instruments (and some non-explosive way of making matter flash out of existence), then this would be practical for space missions, no?

[Nabeshin]

I assume you're talking about my thread, in which we are discussing Newtonian gravity. Newtonian gravity is a non-relativistic theory, so it's not compatible with the principles of relativity. In the theory of General Relativity, gravity waves travel at the speed of light, so there is no issue.

[mr. vodka]

Why would you presume gravity goes faster than light? General relativity says it moves at c.

[Mazerakham]

Sorry. Thank you Nabeshin. I'm just a classical physics kind of guy, haven't really dabbled in this relativity stuff. Thanks.

But I thought someone in your thread was saying that, if gravity waves propagate at c, then there would be some sort of torque on the earth?