Recently,I have found out, that if we consider the speeds at which stars or other space objects move from the point of view of the Earth, we can calculate that they would be faster than light, because they do full revolution in 24 hours, and in that time they do more than a light year of distance. But SR tells us that speed of light is the upper limit for speed of objects in the universe. My question is what is the explanation for this "contradiction"?
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1If you move your eyes back and forth real fast while looking at an object far away, does the object accelerate back and forth? – Adrian Howard Jan 29 '20 at 19:14
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The limitation of material objects to speeds less than c applies only for inertial reference frames. A rotating reference frame is not inertial so that limit does not apply.
There is a related limitation which is more general. That is the requirement that massive objects have timelike world lines in all reference frames. In an inertial frame that is the same as saying that the speed must be less than c, but in non inertial frames the timelike restriction is different, but still valid. It works out to be something like, at any event find the velocities of all possible light rays from that event, the velocity of a massive object will be inside the “region” of velocities defined that way.
Dale
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But even for non-inertial reference frames the limitation holds, but only locally. Right? – Not_Einstein Jan 29 '20 at 18:51
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No. For a general non-inertial frame the restriction may not even hold locally. – Dale Jan 29 '20 at 22:56