Uploaded July 2011 | Updated September 2026, 3 weeks ago

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In videos Relativity 1 & 2 we developed the theory needed to analyze the celebrated "Twin Paradox" which shows how the dilation factor (beta) we needed to introduce predicts that someone who makes a spaceflight will age more slowly than someone who stays on Earth.

Relativity 1: youtu.be/OI9iLDnoLSM
Relativity 2: youtu.be/4t7-1OzTdbY

Relativity playlist: youtube.com/playlist?list=PLF56602BAC693237E