Скачать или смотреть Answering viewer questions about refraction

Why bending, how can light go "faster" than light, and more
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An equally valuable form of support is to simply share the videos.

Much of the last video, as well as this one, is based on the following Feynman Lecture:
https://www.feynmanlectures.caltech.e...

Looking Glass Universe videos on the refractive index:
   • I don't know why light slows down in water  

Timestamps:

0:00 - Why slowing implies bending
3:36 - Recap for how slowing happens
5:08 - Birefringence
6:19 - The barber pole
8:20 - When the refractive index is less than 1

Thanks to these viewers for their contributions to translations
French: LE PRAT Ronan, PyStL
Hebrew: Omer Tuchfeld
Portuguese: rose ✨
Russian: iverid

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These animations are largely made using a custom Python library, manim. See the FAQ comments here:
https://3b1b.co/faq#manim
https://github.com/3b1b/manim
https://github.com/ManimCommunity/manim/

All code for specific videos is visible here:
https://github.com/3b1b/videos/

The music is by Vincent Rubinetti.
https://www.vincentrubinetti.com
https://vincerubinetti.bandcamp.com/a...
https://open.spotify.com/album/1dVyjw...

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testing an addition