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But why would light "slow down"? | Visualizing Feynman's lecture on the refractive index
3Blue1Brown
3Blue1Brown visualizes Feynman's lecture on the refractive index, explaining why light appears to slow down in glass and why the effect depends on color. It builds the idea from waves produced by oscillating charges in the material.
HN considers it among the clearest accessible explanations of what refractive index actually is and how light moves through transparent matter.
6 Hacker News mentions · 2023–2026