When velocities don't add (Relativity)

Relativity is the idea that time and space behave differently depending on your perspective. One interesting consequence is that velocities do not add. They combine according to a specific formula, which is extremely fascinating, and the subject of this video. Chapters: 0:00 Intro 1:27 When velocities do add 4:52 Derivation 8:53 Nice features of the formula 12:01 Tachyons 14:41 Outro #math #science #physics #relativity