Van Flandern: "... the physical quantity heretofore called 'the speed of gravity', which has already been proved by six experiments to propagate much faster than light, perhaps billions of times faster."
"In 1825, Laplace determined that the minimum speed of gravity consistent with observations was at least 10 million times the speed of light, c."
The full equations describing retarded fields were not known in 1825, so Laplace could not have used them to correctly find the propagation speed of gravity. The retarded-field equations were formalized very late in the 19<sup>th</sup> century, I think, and in the first quarter of the 20<sup>th</sup> century it was shown that they stem from the conservation laws and the symmetry required by Noether's Theorem. When TVF uses this calculation by Laplace it is exactly like relying on Newton's calculations for the precession of the orbit of Mercury: an anachronism long superseded both in theory and in observation.
TVF: "A 1997 laboratory experiment by Walker & Dual showed that gravitational signals propagated much faster than light signals."
We've disposed of that one.
The remaining point--the difference between the aberration of sunlight and the vector of gravitational attraction--has been explained nicely in the framework of lightspeed gravitational propagation by Ibisen, Puthoff, and Little.
Really, Clifford Will's challenge to Kopeikin et al is much more substantial. I don't understand how Van Flandern can use something like the Laplace calculation or the Walker-Dual experiment and keep a straight face. Maybe his proposal is really an elaborate satire?
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