How to measure the speed of gravity
Oooh, that looks like fun!
This will take some digestion, but I wonder if a large concrete garage with a really solid floor way up the holler and away from highways would be a suitable lab? 'Cause that describes Rattlesnake Ridge Research.
The apparatus needs an additional feature, a very good Faraday cage between the moving masses and the detector. A couple of electrons of static charge on one of the masses and on the detector would probably exceed the gravitational signal.
I think the detectors described would be problematic, but I'm sure there is something that could be done using a small object of the right form as the detector and using some laser interferometry trick to detect its response. I've used MEMS sensors with micro cantilevers (accelerometers) and would doubt their efficacy for several reasons. Poor stability, for one. Also their associated electronics are usually set up to mask any resonant behavior, by filtering the crap out of the signal.
This will take some digestion, but I wonder if a large concrete garage with a really solid floor way up the holler and away from highways would be a suitable lab? 'Cause that describes Rattlesnake Ridge Research.
The apparatus needs an additional feature, a very good Faraday cage between the moving masses and the detector. A couple of electrons of static charge on one of the masses and on the detector would probably exceed the gravitational signal.
I think the detectors described would be problematic, but I'm sure there is something that could be done using a small object of the right form as the detector and using some laser interferometry trick to detect its response. I've used MEMS sensors with micro cantilevers (accelerometers) and would doubt their efficacy for several reasons. Poor stability, for one. Also their associated electronics are usually set up to mask any resonant behavior, by filtering the crap out of the signal.
I've always though a good place to experiment would be those 2 moons of Jupiter(or was it Saturn) that meet up and swap orbits on a regular basis. The gas giant provides a large electric field for them to do the dance in, perfect for setting up lots of instruments, recording data and making predictions.
CHoff
As a non-physicist, the fact that the force Earth experiences from the Sun is from the instantaneous position, rather than the light-delayed (retarded) position, was a surprise to me when I first learned of it. If Earth was instead pulled towards the light-delayed image of the Sun (as one might naturally assume), we would soon spiral in and be disintegrated, our orbit quickly becoming unstable. :/
Interesting that the propagation-delay of gravity (and of the electromagnetic field) appear to have a sort of automatic correction for moving objects, in a sense.
The experiment is worth doing; just to put any doubt to rest about the "speed of gravity."
Interesting that the propagation-delay of gravity (and of the electromagnetic field) appear to have a sort of automatic correction for moving objects, in a sense.
The experiment is worth doing; just to put any doubt to rest about the "speed of gravity."