In article ,
Rob Dekker wrote:
Finally, a subtle point which some may have missed he what propagates
at the speed of light is *changes* to gravitational fields. The fields
themselves are (loosely speaking) the local curvature of space, and they
don't have to propagate to have effects...

That's an interesting observation.
But is this not similar to stating that although by definition EM fields
(photons) travel at speed of light...

The similarity is superficial; it's a false analogy. The underlying
mechanisms are very different.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
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