While some dream all year of a white Christmas, mathematics aficionados around the country have their own celebration to plan for. It’s National PI Day, observed appropriately enough every year on March 14th.
Pi, if you don’t remember from your geometry class, is the ratio of a circle’s circumference to its diameter. It’s a constant number, meaning that for all circles of any size, Pi will be the same. The first significant digits of the number are 3.14, which makes March 14th (3/14) a perfect day to celebrate it. As an added bonus, it also happens to be Albert Einstein’s birthday.
Pi Day was first organized by physicist Larry Shaw in 1988 at the San Francisco Exploratorium. The observance grew from there. Even Google got into the act in 2010 with one of its famous Google Doodles, the Google logo with circles and mathematical equations superimposed over it.
So how do you celebrate Pi Day? You eat pie (or Pi), of course. To kick off the inaugural Pi Day, Shaw and his colleagues marched around the large circular space of the Exploratorium consuming as many fruit pies as they could.
The town of Princeton, New Jersey, where Einstein lived for over twenty years, also has numerous events like pie-eating and mnemonic recitation contests, not to mention an Einstein look-a-like competition.
If you prefer a more low-key observance, there are plenty of other ways to celebrate, including Pi key chains, t-shirts, hats, buttons and more.
You could even calculate out Pi just for fun. As of this writing, the number has been computed to over a trillion decimal places.