Let’ say; “A” can see and measure a stone falls to the earth let’s say 10 meter per 1 Earth-second. “B” lives at Mercury and can see the same thing. But “B” would do not see the exactly the same, because seen from “B’s” viewpoint time / distance is not the same as for “A”. Let us say time at Mercury would tick half so fast compared to a clock at the Earth. B would not agree it took the stone 1 second to move 10 meter – but have seen that the stone only was moving ½ -mercury second. B will therefore also not see the stone falling 10 meter (as A saw it was falling in one Earth-second), but only that the stones was falling 5 Mercury-meter. It must matter whether the stone was falling 10 meter (from A’s viewpoint) in a certain period, - or only 5 meter (B’s viewpoint), - So the problem is now, how can all laws of nature be the same for all observers. If distances not are changing proportional the same rate as time, - A and B would not agree of the speed of light. Hence distance always must change proportional with time, right?. Both A and B would therefore observe the “same” speed of the stone, - even though a process on Mercury would take relative double so long time measured with a Earth-clock. It is simple math to understand that the speed of the stones anyway “seems” to be the “same” for both of A+B, - but in fact it is not, simply because time is different, and distance too. For example if we on Earth (A) see a photon traveling from the Moon to the Earth, and it take 1 second, - the same event (according to the example) would seen from Mercury only take ½ second. But because distance seen from the Mercury viewpoint (between the Moon and the Earth) is only the half compared to the earth viewpoint, - a photon would hence after one Mercury-second have travelled the double distance meassured 1 second, - with a Earth-clock. Which mean that after 1 Mercury second the photon must have traveled 600,000 Earth-km measured in 2 second with a Earth clock. (Since 2 Mercury-second = 1 Earth-seconds) Let’s return to the real world to make that more clear. After 1 orbit of the Milkyway, a clock at Mercury (B) would REALLY have “lost” 6 years compared to a clock at the Earth (A). The point is that when time/distance not is the same for A and B, how can the laws expressed by Newtonian and Keplerian equations be the same everywhere. At least the gravity constant “G” seems to must be adjusted all the time, since distance is changing all the time. Otherwise the result of gravity will not be right by our feeds compared to ours noses. How can a person that not share ours time-distances share (our) gravity constant (G) ? For example; A person living at mercury and another at the Earth could never agree about the distance - our Sun - travels the MilkyWay, - simple because time is not the same these two places. Evidence is atomic clock wouldn’t lie on these two planets. When 2 such observers cannot agree about distances /radius/ diameter of the Milkyway, - how is it possible for both to use the excact same gravity equations ? If we exaggerate and say that a clock on Mercury ticks half so fast as on Earth, - this would mean that after 1 orbit of the Milkyway we on earth have travels 377,000 Light years, but a person living at Mercury would say the orbit only is the half. Therefore 2 such observers must also get two different result of how strong gravity of the Milky way really is ? How can we then say that the laws of Newtonian/Keperian gravity are the same for both observers?