[Spaceships] Real Life Non-Super Science Reactionless Engines

[Agemegos]

Originally Posted by scc

I'll give you an example based upon my understanding of the problem. You're on a satellite that due to the speed of it's orbit experiences some time-dilation. Now the satellite your on only communicates once per day with Earth, at precisely midnight, Greenwich Mean Time, with asynchronous computer transfers. One day you notice that the daily upload from the ground has started early, you realize that it's because of relativity, but no special frames of reference says that the clocks on Earth are running slow, not yours, and that causality has been broken.

I don't think you have that right. "No special frames of reference" is one of the postulates that you derive relativity from. Relativity is never going to contradict one of its own postulates.

In your example the satellite is constantly accelerating, and the ground server is supported in a gravitational field, both or which bring General Relativity into play. You're talking about accelerating frames of reference, and unlike straight-line motion acceleration is absolute. The statement that there are no privileged frames of reference is more strictly that no inertial frame of reference is privileged.