Hyperbolic Geometry, Berkeley Math Circle

These are my notes from a class at the Berkeley Math Circle on October 31rd, 2024. You can find an accompanying handout here.&#xA;Today we&rsquo;re going to be talking about hyperbolic geometry.&#xA;But before we talk about that, first we have to talk about geometry. Ordinary geometry takes place on an infinite flat plane, like the whiteboard. We call this thing the Euclidean plane, after Euclid…