Billiards in the hyperbolic plane video
The gist
The 2swap channel's video on hyperbolic outer billiards has drawn 3,947,755 views and 101K likes.
It walks viewers from bouncing balls to a geometry where pentagons tile like squares.
How it unfolded
- 2007Richard Schwartz first discovered the shape, the Penrose Kite, proven to feature unbounded orbits in outer billiards.
- Sep 20, 2026The video "i'm so bad at billiards that i ended up in the hyperbolic plane" was posted on the 2swap channel, reaching 3,947,755 views and 101K likes.
- Oct 30, 2026User surprisetalk submitted the video to Hacker News, where it had 4 points an hour after posting.