According to relativity, a future event X in one inertial frame lies in the present of another inertial frame, assume for example that the event is the decay of a radioactive atom, doesn't this imply that whatever laws of physics we use to describe such decay must be deterministic? After all, if the decay already happened in the other frame, then it means that the result of this event must already be decided before I measure the atom, but doesn't this contradict quanutm mechanics?
EDIT: By "deterministic" I don't mean that the future state of the particle can be determined with certainty, I mean the fact that the quantum state of the particle cannot fully determine the dynamics of the particle
