Today is pi day! Before we delve into that 3.14 slices of pie and many nerd jokes (even the US Congress designated today with a resolution to officially recognize pi), let’s talk about the one of the most significant symbols in mathematics.
We know π as a specific ratio of the circumference to the diameter of a circle. π as a number is irrational with no patterns in its calculation. While computer scientists have calculated π to billions of places, but it’s always a mystery as to the next number.
Even though we simply refer to π and its relationship to C/d, π appears all over nature: The double helix, concentric rings of a pebble splashing, waves, the Heisenberg principle.
But π also has problems. While true π =C/d, π is more commonly used as 2π, which is tau (τ). And τ is the ratio of circumference to radius (τ = C/r).
The famous web comic, xkcd trying to rectify π and τ.