The Twin Clock Paradox is only inexplicable for the situation where the actual relativity mathematics are not fully understood.
The Problem:
If a rocket leaves relatively stationary earth and travels a sufficiently great distance with a velocity at a significant fraction of the speed of light, and then later returns ostensibly "younger" than what was left behind, the question therefore arises if all motion is indeed relative, why then could not the earth be considered as having left the rocket and therefore upon the mutual return of earth to the rocket be shown equivalently also as "younger"?
To allow or block links to the Internet in PDFs: https://helpx.adobe.com/acrobat/11/using/allow-or-block-links-internet.html
