Thinking Outside the Plane: metafilter.com/183649/Thinking

Interesting roundup of 3d solutions to 2d problems, starting with Tarski's plank problem: Can you cover a diameter-$$n$$ disk with fewer than $$n$$ unit-width strips?

Sadly, they missed the 3d proof of Desargues' theorem: en.wikipedia.org/wiki/Desargue

There's also a 2d-3d connection with Miquel's six-circle theorem but I think it goes the other way: 11011110.github.io/blog/2006/0

A Mastodon instance for maths people. The kind of people who make $$\pi z^2 \times a$$ jokes. Use $$ and $$ for inline LaTeX, and $ and $ for display mode.