2000 years unsolved: Why is doubling cubes and squaring circles impossible?
Today’s video is about the resolution of four problems that remained open for over 2000 years from when they were first puzzled over in ancient Greece: Is it possible, just using an ideal mathematical ruler and an ideal mathematical compass, to double cubes, trisect angles, construct regular heptagons, or to square circles?
00:00 Intro
05:19 Level 1: Euclid
08:57 Level 2: Descartes
16:44 Level 3: Wantzel
24:00 Level 4: More Wantzel
31:30 Level 5: Gauss
35:18 Level 6: Lindemann
40:22 Level 7: Galois
Towards the end of a pure maths degree students often have to survive a “boss“ course on Galois theory and somewhere in this course they are presented with proofs that it is actually not possible to accomplish any of those four troublesome tasks. These proofs are easy consequences of the very general tools that are developed in Galois theory. However, taken in isolation, it is actually possible to present proofs that don’t require much apart from a certain familiarity with simple proofs by contradiction of the ty