Plays with YouTube's privacy-enhanced embed Why No One Has Measured The Speed Of Light
6 HN users recommended this explainer in 7 different months between 2020 and 2024.
2007–2026
3 strong recommendations 4 recommendations 10 citations HackerTube score 8.5
Used as the standard reference in threads about light speed, clock synchronization and untestable assumptions in physics.
Veritasium explains why the one-way speed of light has never been measured, only the round-trip speed, since measuring it requires synchronized clocks that assume the answer. It explores the implications for relativity.
Pull quote: “I found the video very compelling even as a thought experiment.” (HN, 2020)
Also tagged: one-way speed of light, speed of light, special relativity, clock synchronization, veritasium, physics
What Hacker News said
17 labeled comments from the HN archive; up to 20 are kept per video, favoring different commenters. Each one links back to the original thread.
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