Okay, a couple of people have now mentioned something about acceleration
causing one frame of reference to be more absolute then another (for
lack of a better way to say it). Such that if one person accelerates and
then decelerates, the frame of reference that did not accelerate is the
right one and the one that did accelerate accelerated out of the right
frame in then back into the same frame causing the twins to age
differently. Normally I would accept that. (I am not nearly smart enough
to not accept it.) However, an example I found online while reading up on
all this is making me wonder. (Though, I may have just not been hearing
the explanation people were trying to give right.)
I forget what exactly it was trying to explain, but the example went like so:
If you have a platform you can rotate and you place a plate of milk on it,
and then spin the platform, the milk will slosh out of the plate as the
pull of the force (acceleration/simulated gravity) pulls it out of the
plate. If, however, you have the same platform with the same plate of
milk on it and you spin the rest of the universe...the milk will still
slosh out over the edges as you accelerate everything around you.
So there is still no right frame of reference, and there is still no way
to tell which accelerated and then decelerated: the universe or the
platform. However, the effect was the same in that the milk sloshed out
over the edge of the plate towards the rest of the universe. I think
thats whats throwing me off; I cant see why the effect would be the
same regardless of what did the accelerating.
Thank you everyone for all your responses with this. Its been a big
help. I still have a ways to go before I get it, but I am definitely
closer than I was a week ago.