symmetry
2 free lessons tagged symmetry across Math. Each one is a short sequence of focused steps with narration and a five-question quiz at the end — take them in any order, no signup required.
Symmetry Groups: Crystals, Conservation Laws, and Neural Networks
Group theory earns its keep when a symmetry argument settles a physical question no calculation was going to answer. This lesson covers group actions and counting up to symmetry, why crystals cannot have five-fold rotation and what happened when one did, Noether's link between symmetry and conservation, and how the same idea is built into modern networks.
What a Group Is, and Why the Axioms Are So Bare
A group is a set with one operation obeying four rules, and that deliberate poverty is the point: anything proved about groups holds for rotations, permutations, integers, XOR and Rubik's cube at once. This lesson builds the definition from symmetry, works through the symmetries of a square, and shows where groups already sit in code.