How does light 'know' the shortest path?

Joke edit lol Graham's number is one of the largest numbers ever used in a serious mathematical proof. It was introduced by mathematician Ronald Graham while solving a problem in an area of mathematics called Ramsey theory. To understand how unimaginably huge Graham's number is, compare it to numbers like: One million = 10⁶ One billion = 10⁹ The number of atoms in the observable universe ≈ 10⁸⁰ Graham's number is so much larger that even writing it in ordinary decimal form is physically impossib

Number Challenge Final: How to Do the Number Challenge