### Pi Day 2018: Easy as Apple Pie

## Rev1 celebrates a delicious Pi Day

Today, March 14, is Pi Day—the one day every year where the month and day match the commonly used numeric sequence of Pi (3.14).

It’s not an “official” federal holiday, although the House of Representatives did give Pi Day a ceremonial vote about 20 years ago.

Be that as it may, Pi Day is celebrated all over the world by math aficionados and plenty of other people, too.

First, a quick refresher on p: It’s the ratio between the circumference of a circle and its diameter.

No one invented pi. It came from nature.

Archimedes, the ancient Greek mathematician, is widely considered to be the first to calculate an accurate estimation of the value of Pi. Builders and mathematicians have been applying Pi for thousands of years in far-flung reaches of the globe, from ancient Babylonia to Gaza, from China, to India, from Germany to Wales.

Interestingly, one of the greatest mathematicians of all times, Albert Einstein was born on March 14, 1879—after p but before Pi Day.

Pi is like the work of an entrepreneur starting a company—it never ends. Last year, after 105 24-hour days of calculation, a computer broke the world record for computing Pi with an addition 9 *trillion* digits of Pi. Interesting, but not very useful. NASA, for all its precision, typically uses just 15 digits of Pi.

There’s another similarity between Pi and starting up a company—there are interesting patterns inside the digits of Pi—but there is no constant rule governing the sequence.

Record-setters like to memorize Pi—the Guinness World Record is held by a fellow from China who recited 67,890 digits. Here’s a YouTube video of 11-year-old Austin Baio breaking the world record of quoting for his age group.

As far as I know, no one at Rev1 memorizes the digits Pi, but we do celebrate the day—by baking and serving pies.

My favorite pie is my mom’s homemade apple pie. She got the recipe from her mother, who we all called Bonbon. I keep Bonbon’s recipe in a file on my computer—sharing it with you here. Using a computer as a recipe box would probably make Bonbon shake her head.

What makes me shake my head is that whenever I go to make this pie, my mom always reminds me of a step that isn’t in the recipe. You are supposed to put four dollops of real butter on the top of the pie.

Now as a mechanical aerospace engineer, I get centimeters and milligrams, and certainly Pi, but there is no measurement for a dollop.

What I have learned about dollops over time, is that a little more butter sure makes a better pie.