in the weak field [our solar system or anyplace where dt_r orbit ~ dt_GR bookkeeper]. But Newton's result is useless for strong field physics and for exact calculations in the weak field [like the calculations needed for the GPS to work properly]. I suspect if Newton was alive he would be pleased to understand why this is a fact of nature. When I first read something written by Stafford he said 'clocks don't measure time intervals' and that Einstein goofed the way he modeled time in relativity. The littany of crackpots who really don't understand what a theoretical model is. Theoretical models are free creations of the human mind created to model and predict how stuff [natural phenomena] behaves within a domain of applicability. The only requirement is that they are testable [the predictions can be falsified] and that they are useful. Even theoretical models which have been falsified can be useful as evidenced by Newton's result. I didn't write that for your benefit because you already understand this. I figured Stafford's complicated mumbo jumbo wasn't worth reviewing once he made it perfectly clear he didn't know what he was talking about. He screams that at folks before they even get to his derivation. The prediction Stafford made for you proofs he has had his head burried in the sand for a long time. Sorry about being so tough on the guy but I can't stand the elitist attitude he has towards the other posters in this forum.