> Is there a mathematical reason why No. Here's another topological map of the contiguous US that's all rectangles, arranged in a triangle: https://www.reddit.

> Is there a mathematical reason why No. Here's another topological map of the contiguous US that's all rectangles, arranged in a triangle: https://www.reddit.com/r/MapPorn/comments/gy2jq6/the_topologists_map_of_the_contiguous_united/ https://www.reddit.com/r/MapPorn/comments/gy2jq6/the_topolog... I'm not sure how much I'd overthink this map, since it appears to have been created as a puzzle for children to help them understand the concept of topology: https://www.1001mathproblems.com/2015_11_01_archive.html https://www.1001mathproblems.com/2015_11_01_archive.html > Does that notion generalize to all border maps and if so why? No. > Is it related how border maps can all be colored with only four colors? If you're talking about the four color map theorem? Instinctively, my answer's no, but it might be a fun thing to prove.