This is probably answered many times, but my confusion is the following.
In special relativity it is said that there is no preferred coordinate system. Does that mean that for the people at rest (any rest frame of reference) things happen at same rate ? But just are seen from other system as delayed. So that people live to same age or particles decay at same life times in any rest frame.
The GPS satellite clocks run at different rate as seen from earth. But the atomic clock should run in space at same rate as the one on earth. (not taking into account the gravity effects)
With all of the above said my question is simply: can we conclude from having same physics in all rest frames (that are non accelerating) that it does not matter with what speed we travel we should always have same time rates for particle decays, life span.. Yes, no answer will be perfect.