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Pi: Not Just a Number

3.1415 on 3/14/15

by Lt. Loren Terry, Defense Media Activity
13 March 2015 Today is not just another Saturday. It's Pi Day. But it's not even just another Pi Day. For most of us, there is something you would rather forget from your high school days. That epically horrible dodge ball game, the time a bird decided to relieve itself on your shoulder during lunch time, the first date that didn't go so well, or for some, high school geometry. But here's why those people should give it another chance.

And as the sun arose today, it ushered in a Pi Day of all Pi Days. Yes, it's 3/14, but it's also 3/14/15. Never again in our lifetimes, or our children's lifetimes, will this sort of event happen again.

Numbers are all around us; they are the language of the laws that govern our universe. Just as much as Monet, Shakespeare, Bach and the Rolling Stones have defined our culture, math defines us just as much.

But how often have you heard, "when will I ever use algebra again?" Replace 'algebra' with geometry, complex variable calculus, or differential equations - well, maybe not the last two - and you have heard it all. But you would be wrong, my right-side-brain-dominant friends.

3.141592... or Pi, the ratio of a circle's circumference to its diameter, is an irrational constant which continues infinitely in decimal expansion; it goes on forever, and it's everywhere.

It's how we approximate the size of distant planetoids only detectable by the wobble they inflict on their parent star; it's how we calculate the search area of a search circle when a plane or ship disappears into the ocean; it's used to shape the neck of the saxophone that plays the soft jazz at your friend's wedding; it's how they figured out what size to make the cup holders in your car; and it's how they decided just how large of a beer bottle was comfortable for a human hand to hold.

Pondered by the ancient Egyptians and Babylonians, pi, or some variation of it, has been used ever since man tried to draw the first circle. And how many circles do you see every day? Your coffee cup, your key ring, your salt-encrusted tire rim - they're everywhere. So when the Greek mathematician Archimedes sat pouring over equations by candle light and figured it all out for us, it changed his world. In the flash of a synapse, he realized there was so much more to the macroscopic and microscopic world, with much more to be discovered - mind blown.

As nerds, college professors, navy nukes and pretty much every NASA employee dives into a themed pie or tells the time in radians of pi tomorrow, we should not forget what we are really celebrating: the idea that our universe is begging to be explored; that there should be no bounds to human endeavor, and that a life in which we are exploring and discovering parts previously unknown is fundamentally better than one in which we are not.

So today on the Pi Day of all Pi Days, have a piece of pie, find an excuse to tell someone it's 1600 by saying it is two thirds Pi, and take a minute to think about what Pi Day is all about - at least that's what I'll be doing.