Hi all! This is a neat forum; wish I'd found it sooner... I'm writing a short scifi story, and am having trouble understanding time dilation, which happens to be an integral part of the story. Anyway, here's my question: Its common scifi staple where starfarers travel at close to the speed of light from point A to point B, and back. Upon their return to point A, the travellers aged little compared to those who remained on A. Since motion is relative (so you could say that the travellers remained in place, while point A accelerated away), then why couldn't the folks who remained on A be the ones who experienced a shorter passage of time? Can someone please help? Thanks!