The journal · A bit of maths
🌐 En français →Maths machines in your hand
Move a slider, and a big idea comes to life. You grasp it first — then you take on the challenges, from age 6 to 18. A growing set of machines, translated one by one.
A bit of maths
Simple stories, maths that go far — great theorems made playable.
Why are bubbles round?
The isoperimetric idea: same string, the circle holds the most. The score 4πA/P² climbs to 1 — Yilin Wang's childhood question.
🎛️ Blow the bubble →
The Kakeya needle
Hong Wang, 2026 Fields Medal: the most economical U-turn — the swept area halves with every trick, all the way toward 0.
🎛️ Spin the needle →
Every machine is a door: it makes you understand — then it sends you off to practise.