Quoted By:
If you mean objective time experience then the answer is that the difference in our personal speed is so small that the difference in time caused by special and general relativity is so small that over your entire lifetime you might only experience like 0.0000000000000001 second difference from another human.
If you mean subjective time difference then you need to realize that humans are actually despite common perceptions, extremely similar in cognitive ability. The dumbest non-handicapped human and the smartest human ever born have basically the same brains and the same abilities with only minor differences in ability if you take a deeper look into it.
Thus the subjective difference in the experience of time will be very minor. Of course we can't know for sure what other people experience.
Once we have digitally uploaded people is when it starts becoming interesting. Then you'll have people experiencing a million years subjective time in a couple of objective hours.
