This article discusses a special case of the twin paradox in which the accelerated twin ages faster than the inertial twin: http://www.physorg.com/news163738003.html According to the article, if you have two observers orbiting a planet, and one of them decelerates to land on the planet, than the twin who doesn't decelerate will age slower. But then they say this: Absolute standard of rest? That just doesn't sound right. But if it's wrong, why IS the inertial reference frame aging slower? The article claims that it's okay to talk about absolute reference frames in GENERAL relativity. Is this true?