Main Question or Discussion Point
After looking at the "doppler effect" explanation of the twin paradox, I'm under the impression that the difference in the age of the two twins has to do with the part of the diagram where one of the twins is accelerating. But, my question is, what about the "coasting" part of the diagram? So, if I were to accelerate two particles in exactly the same way, but, allow one of the particles to coast 10 more years in the lab frame, but stop the other one immediately after acceleration, would they both end up aging the same amount? If we cut out the coasting part of the diagram in the middle, would that make a difference?