in laymans terms, (subject to minor variations through human error) the two twins are always in indentical frames of reference,so when they meet up it will all add up and there will have been no net relativistic effects. however during transit they would each observe identical things in the other as the other was observed to approach light speed and relativistic effects would be taking place they would each observe time to be passing slower for the other. the key thing is that in each case this will be identical to both observers at each point and they are always travelling at the Sam velocity and thus it all cancels out in the final case.
ETA:however if you put in a 3rd neutral observer who wasn't travelling then effects would be seen. he would see time slow down for both as they approached C and they would observe the same for him. but because of the difference in reference frames, it wouldn't cancel out and less time would have passed for them than for him despite the fact that in each case they would have both observed time dilation in the other. also of course the two twins would see the other approach C long before either would think so relative to the neutral observer. each is accelerating at 1G but will oberve a 2G acceleration relative to the other.
it's all about frame of reference rather than observation at the end of the day. when these differ there are net effects when they don't there are not. it's part of what I have been saying elsewhere, it's all about relative velocity and you can only state such relative to something else and observation is based upon this, but frame of reference isn't something that depends upon the observer it's a physical thing. I hope you can see the distinction here.
Last edited by malaidas; 2017-Mar-10 at 10:26 AM.
You're really not going to like it, the meaning of life the universe and everything is.... is.... 42!
is that all you have to show for 7.5 million years of work?????
it was a tricky assignment.
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