A massive thank you to Prof. Steven Strogatz for his expertise and enthusiasm.
00:00 - One rule that replaces all of physics
00:51 - The problem of fastest descent
05:09 - Fermat's principle
07:17 - Bernoulli's solution
10:38 - Maupertuis' principle
12:28 - Maupertuis attacked and ridiculed
14:01 - Euler & Lagrange to the rescue
17:22 - The general approach to solving these problems
19:32 - Writing the principle into its modern form
23:17 - Why the principle works
27:08 - Another way to do mechanics
30:19 - A “spooky” breakthrough