I suppose if you try to explain the existing theory, with a thought, this is not against the forum rules.. So far as I know is our clock based on the rotation of the earth. So our time has defined in that way. Everywhere on earth is our clock running in the same rate. Suppose somebody is stationary in space somewhere and is observing our earth which has a speed compared to that person. Suppose that person has synchronised his clock in some way on a moment. That person would see dilated time and length contraction observing our earth from that person’s location (and vice versa because of symmetry, in fact based on the speed difference, for both the same). Suppose our earth would get a higher speed. I would think that person would observe a slower rotation and a higher dilated time. Both could be explained by a force observed by the observer, as well for the rotation of the earth as physically (down to atom level) for all kind of clocks which would be running slower. And like on the earth with the old speed, also on the earth everywhere with the new higher speed. Light waves emitted from earth would be influenced too by that force in ration (suppose very small mass) and would travel lesser distances (but lesser distances / slower time = still the light speed c). Relativistic Doppler would be observed. Indeed is at the same moment the duration observed smaller with a higher speed than with a lower speed (suppose two earth’s with different speeds for the observer). Because of the force everything will be observed slower. Is duration in this way difficult to understand or do I see something wrong again?