Happy Pi Day, math lovers

It's 3.14, and that means it's time for the official Pi Day celebrations to begin.

Get out your favorite circular objects, people, it’s Pi Day 2011!

As the math and science enthusiasts among us already know, March 14 (i.e. 3/14) is official Pi Day — a day to celebrate the number Pi, identified by the Greek letter p, which is used to calculate the circumference of a circle.

Pi is most often shortened to 3.14. But because the number is both irrational and transcendental, it “will continue indefinitely without repeating,” as the official Pi Day website, PiDay.org, kindly explains.

With the use of handy computers, Pi has now been calculated out to over 1 trillion digits past the decimal. It is Pi’s mysterious nature — the fact that it can never be entirely known — that has helped generate the adoration for it held by the mathematically inclined.

The famous symbol for Pi, p, was first used by Welsh mathematician William Jones in his work Synopsis Palmariorum Matheseos, which was published in 1706. It wasn’t until its adoption by Swiss mathematician Leonhard Euler in 1737, however, that the Pi symbol gained widespread popularity.

So, what is the purpose of Pi Day?

“It’s primarily a chance to have fun with the topic of math and science,” David Blater, author of The Joy of Pi, tells Time.com‘s NewsFeed blog. “And while it celebrates Pi officially, it’s more of an excuse to get excited and show the fun side of math and science.”

The first Pi Day was celebrated in 1989 at the San Francisco Exploratorium, which remains one of Pi Day’s primary promoters. Today, Pi Day celebrations take place in countless grade schools across the country.

While a wide variety of Pi Day celebrations are acceptable, some of the most popular include circle-measuring parties, watching the movie Pi, Pi recitation contests (to see who can accurately recall the most digits) and, of course, eating actual pie!

It's Pi Day

t may not be marked on most calendars, but if you're a math nerd (or a nerd in general -- of which we count ourselves, obviously), you know what March 14th is. It's 3/14, otherwise known as the first three digits of Pi. That's since become a minor geek holiday of sorts, and has prompted some fairly unique celebrations over the years. One of the latest comes from musician Michael John Blake, who interpreted Pi to the first 31 decimal places as musical notes and turned it into a song -- played at 157 beats per minute, no less (or half of 314). As it turns out, however, Blake wasn't the first to come up with the idea -- composer Lars Erickson wrote his own "Pi Symphony" a few years back, and has now sparked a bit of a copyright spat on YouTube over who actually owns the rights to Pi in musical form. Head on past the break to check out both versions for yourself.

Happi Pi day

For Pi day, let me plug David Blatner’s The Joy of Pi, a short tome of fun facts about pi, whose main advantage is that it cites me, saying something along the lines of “Sure, memorizing digits of pi isn’t useful, but saying that math has to be useful is like saying that the English language is only good for ordering pizza.”

What was that all about? Back in 1996, I and some friends made up a little mnemonic paragraph to remember the value of pi to 167 digits. (There may be a slight error in there; I no longer remember.) That item was picked up in a number of places, including The Scientist and Ivars Peterson’s MathTrek column.

Otherwise, I’ve never profited from this invention, so I share it with you now for free lest it be lost forever. Of course, there are a great many pi mnemonics out there, some much longer than 167 digits; see, e.g., Poe, E.: Near a Raven (740 digits), which isn’t even the longest.

In other news, if you type in “pi” in the iTunes store, you find a number of interesting songs called “Pi”, some of which sound interesting. Downloads of the day?