Tony: You're unable (or unwilling) to explain what you meant? Okay. I'm not surprised. Yes. We know that Newton was wrong. We have, for instance, detected gravitational waves. Is it relevant to what we have been discussing? Did you read my post #33, above? Is there something there that you didn't understand? Why don't you tell us? Here's a link to some of the relevant maths. You can do the calculation yourself and tell us your result: Riemann curvature tensor Don't tell lies, Tony! Yes. Without correcting for time dilation effects, the GPS system would not be able to locate objects on the Earth with the accuracy that it demonstrably has.