Draw me if you can: Constructions with Euclidean tools

Abstract: How much geometry can you squeeze out of a straightedge and compass? Trisect an angle? Maybe not. Draw a regular 17-gon? Absolutely. The ancient Greeks figured out how to draw sums, differences, products, ratios and square roots of given lengths, as well as how to construct some geometric figures from others, but it took two millennia to finally completely close the case of constructible polygons. In this filler episode, we’ll cover the main ideas: which shapes can be drawn, which can’t, and why.

Mathematics

Audience: general audience

Gothenburg PhD seminar

Series comments: Rooms and times may vary, please check the latest update. In-person only.