2:55:39
Richard Behiel
The Twin Paradox: Time Travel, Explained Visually
A near three hour visual masterclass that derives the twin paradox from one strange fact: light has a single speed for everyone. Behiel builds time dilation from a bouncing light clock and the Pythagorean theorem, then generalizes it until it applies to all matter, which he frames as bound energy that has less time for time when it moves. He resolves the paradox not with acceleration but with the tilting of the present moment when the traveling twin turns around, and grounds the whole thing in real evidence: GPS, muon rain, the LHC, and the Hafele-Keating atomic clock flights.