I've been trying for a long time to get an answer to the question, "What is the physics or mechanical explanation of contracting physical objects and the distances between them?" I understand that the phenomenon is theorized to depend on different observations from different frames of reference going at relativistic velocities and contracting in the direction of travel of the observing frame. But how can different observations of the same object or distance change (shorten) that physical object or distance? Example: Earth's diameter is nearly 8000 miles. Special relativity (SR) theorists claim that a frame approaching at .866c would measure its diameter (in the direction of the approach) to be about 4000 miles. But of course Earth's diameter would not actually physically shrink by half in that case, so how is the paradox resolved, given that all frames are said to be be "equally valid" in SR, and also that "length is not invariable" (it varies.) How is "proper length" (the 8000 mile diameter) reconciled with frame dependent length (4000 mile diameter) in this case? As for distance between objects, same question... Example: The astronomically determined distance to the Sun (ave. AU) is about 93 million miles. But a frame theoretically passing through our solar system at .866c would, according to SR, measure the AU to be about half that. Yet Earth obviously does not move 46.5 million miles closer to the Sun. I know that length contraction is the math reciprocal of "time dilation," but how can a slower ticking clock in that fly-by frame cut the actual distance to the Sun in half? Ps: If that clock showed only 4 minutes elapsed time for the Earth-Sun journey, would that mean that SR claims that the frame (future ship or whatever) made the journey twice as fast as light... which requires 8+ minutes to go the 93 million miles. I would very much appreciate help in resolving the above related time dilation and length contraction paradoxes. Thanks.