Charlie Brown’s head. Pizza. Apple, cherry and rhubarb.
What all of these things have in common is Pi, the ratio of the circumference of a circle to its diameter.
Today the world over mathematicians, pizza lovers, fruit and savory pie eaters along with Peanuts fans can come together in celebration over the Greek letter π, also known as 3.14159…
Richard Wilders, a professor of mathematics at for 36 years, said that he favors apple pie but will gladly eat any type of pizza with some sort of meat on it such as pepperoni or sausage.
When it comes to π he is quick to point out that Pi is irrational. Which does not mean it isn’t realistic, merely that there is no way to write it as a fraction.
“There are only three numbers that have a name like that,” he said. “In that sense it’s kind of cool.”
Joining Pi there are the square root of -1, known as little i and little e, which is roughly 2.7, he said.
Why Charlie Brown has been called a block head when his head clearly has the roundness of a circle has not been solved through mathematics. But, the search for Pi, not the fruit kind, began back around 400 B.C., Wilders said. Archimedes was one of the first to try to solve the riddle.
Though a circle seems like such a simple object, it isn’t, he explained.
“The fact is that any time there is a circle there is a Pi lurking there,” he said. And, without Pi many formulas in physics might not have been found.
According to the Pi Day website, Pi s an irrational and transcendental number, meaning it will continue infinitely without repeating.
Wilders said competitions take place to see how far numerically a person can memorize and recite. One record holder was able to memorize 67,890 digits, which took him more than 24 hours to recite.
One has to wonder if he had a taste for pie after reciting Pi?
Whereas, that man was only able to get to 67,980 digits, computers are able to calculate Pi to 1 trillion places after the decimal, according to the folks at Pi Day. Wilders said Sir Isaac Newton computed it to 16 decimal places, “which is pretty darn good for having nothing but a piece of paper and a pencil.”
Up at North Central College, there will be a small celebration taking place, said Mary McMahon, associate professor of mathematics and the math education coordinator at the college.
Today, alums will come back to the school and celebrate. The students in question are mathematics student teachers that will share what they have been learning at their respective schools.
The student teachers will share Pi Day poems, songs and jokes, such as: “What do you get when you take a bovine and divide its circumference by its diameter? Cow Pie.”
McMahon started the event on campus back in 2004, she said. Scientists have Bohr Day (as in Niels Bohr), so the mathematicians should get a day to celebrate too.
“I started it on the campus because of the fact that it was the end of the student teaching term for many students and I wanted to celebrate with them; celebrating that milestone and that they would soon be stepping into the math classroom,” she said.
For McMahon, along with liking π, she also enjoys vegetable pizza and chocolate silk pie.
The North Central party gets underway in the late afternoon, she said, adding several area high schools would also be holding celebrations.
Though North Central's party won’t get underway until late in the day, Wilders said when planning a party, “if you do it right you start it at [3-14] 1:59 p.m.”
More about Pi(e):
Pi in the movies: Darren Aronofsky (better known lately for Black Swan) directed Pi, a film about a paranoid mathematician. It’s dark, but fascinating.
Pie at the store: Whole Foods Market will celebrate Pi Day with deals on Pie, according to the Naperville Store's event board.
Pie at the restaurant: "Pie Rush" Day at Bakers Square is on Wednesday, but you can always get a slice at the chain.
National Pie Day: Celebration of the actual fruit pie takes place on Jan. 23 every year.
Favorite Pies: According to Serious Eats the top three pies in the U.S. are apple, pumpkin and chocolate cream, followed by cherry in 4th place.