Insisting that two observers that go from event A and both arrive later at event B must have experienced the same elapsed time is to adopt the 'absolute time' position. Relativity does not require that the experiences must be the same, which is why the OP is convinced it is wrong.
(I'm sorry if you don't get it — it is blindingly obvious to anyone who has actually studied relativity to see what the theory actually says. Please try to engage rationally and do some reading before rejoining. I'll give you a couple of weeks and then I will read your responses to see if you have it worked out. :up: Good luck. )
It isn't just "event A" and "event B". It is ANY two (or more) events you care to name. I don't care what they are or how long the duration between them. You pick ANY NUMBER OF EVENTS WHATSOEVER and everyone and everything that existed when those events happened will have existed together with the events and with each other.
Did the observer at the top of the mountain exist when the clock at the bottom of the mountain struck noon on 9/11/17?
Yes or no?
Notice that the question can be directly answered NO MATTER WHAT HIS CLOCK READS! The time registering on the clock at the top of the mountain is completely irrelevant to whether both the clock and the observer at the top of the mountain existed when the clock at the bottom struck noon on a particular day. Both clock and both clock observers, as well as the top of the mountain and its base, all exist together in the present. No matter how fast or slow you claim they are moving through time relative to each other, they all arrive at the present in perfect unison.
The point here is that you accept a contradiction! You want to say that something has happened and that it hasn't happened.
P.S. I realized after I had this typed up, who it was I was responding to. I suppose I'm fine with continuing the discussion if you can stay on topic without insulting my intelligence.