Although I’m sure we all know this, it may be best to remind ourselves that the symbol used by mathematicians to represent the ratio of a circle’s circumference to its diameter is the lowercase Greek letter Ï€. This may also be written as pi or Pi (“pronounced “pie”), which is derived from the first letter of the Greek word *perimetros*, meaning “circumference.”

Quick question: What’s the value of Pi? You probably answered 3.142… and kept on going for a bit depending on how often you use the little scamp and for what purpose. The reason I ask is that there has been some debate about this, as I discussed in *Should Pi = 3.14… or 6.28… or 1.57…?*

Pi is an irrational number, which means it represents a real number with a non-repeating pattern that cannot be expressed as a ratio of whole numbers. Ever since the first irrational number was discovered (possibly around 500 BC, when Hippasus of Metapontum proved that the square root of 2 could never be expressed as a fraction), certain members of society have treated them with suspicion.

I’d like to say that Pi is my favorite irrational number, but I don’t want to upset the others.

Did you ever read *Contact* by Carl Sagan? This involves the folks at SETI (search for extraterrestrial intelligence) picking up a signal containing a series of prime numbers from a star system 26 light years away. Eventually, the decoded message reveals instructions to make a weird and wonderful machine.

A small group of people — including our heroine, Eleanor “Ellie” Arroway — enters the machine, which powers up and transports them through a series of wormholes to a massive station near the center of the Milky Way where they learn all sorts of cool things. Unfortunately, when they return to Earth, they discover that no time has passed, all of their video records have been erased, and no one believes they actually went anywhere (bummer).

With nothing better to do, Elli creates a program to compute the digits of Pi to unprecedented lengths. Eventually, the computer detects and displays circle rasterized from 0s and 1s that appear after 10^20 places in the base 11 representation of Pi. Amongst other things, this suggests that intelligence is behind the universe itself.

The reason I’m waffling on about all this here is that my chum, Jay Dowling, just send me a link to this Song from Pi video on YouTube.

As you’ll see, the mastermind behind this video created the melody for the song by taking Pi and assigning each number to a note on the A harmonic minor scale, after which harmonies were added using the left hand.

The result is strangely captivating, as are all the tidbits of trivia and nuggets of knowledge that are displayed while you’re listening to the music.

Well, now that Pi has been “bagged,” I suppose someone should do similar treatments for the square root of 2, Euler’s number (e), and the Golden Ratio, which is usually symbolized by the lowercase Greek letter phi (Ï•). I’m a tad busy at the moment, so maybe you could take this one — what do you think?