Why is the invariance of light a problem?

[russ_watters]

Of course yes, if it were so simple. But if you accept the assumption that all processes in the world can be altered in a tiny fraction of the world you are opening up a n endless Pandora-box of trouble.

Why do you believe that when others are saying exactly the opposite is true? How is needing a lot of different explanations simpler than only needing one?

What happens to processes (nearly all) that are time-dependent? forces like gravity and electric?
A ship orbiting the Earth at 9.9999.. c vould have no gravity, no atomic bonds, what would happen to radio communications? etc...

Nothing. That's the point: relativity is what enables them to always work the same way. That is in fact one of its postulates.

 

[Dale]

If time is, say, 1/10 of the time outside the ships should get 1/10 of the regular acceleration

I would have to work it out, it may be a different factor. However, the short answer is that coordinate acceleration can indeed differ from proper acceleration. All frames will agree on proper acceleration, but, obviously, different frames will disagree on the coordinate acceleration.

When the radio waves are picked up inside the ship they they get in at a shorter wave but the words jam ten times quicker, but they cannot understand English any more because their brain is 10 times slower, right?

Sure. I don't see why you think that a persons inability to understand a blue shifted transmission represents a problem for a physical theory.

They cross the moon 10 times in a second ( their second) so, as the know the the orbit is 2π c, they are moving at 10 c in their frame?

By definition they are at rest in their frame.

The math guarantees that an object which has a timelike worldline (slower than c in a coordinate independent sense) will have a timelike worldline in all frames. Similarly, an object with a lightlike worldline (traveling at c in a coordinate independent sense) will have a lightlike worldline in all frames.

Furthermore, if two timelike objects pass right next to each other then they will both agree on their relative velocity at the meeting.