Re: Where did PI come from. Who first discovered it?

"Pi" (usually represented by the Greek letter) is the ratio of the circumference (the distance around) to the diameter (the distance across) of any circle. It is a constant of nature, and appears in many seemingly unlikely places including quantum mechanics.

Pi has been known since ancient times, and the ancient Greeks discovered that it is an irrational number, which cannot be represented by a fraction, the ratio of two whole numbers like 3/4 or 15/33. The ancients also discovered that 22/7 is a pretty good approximation of the true value of pi.

There is a lot of history wrapped up in this number; you might try reading John Barrow's history of mathematics, "Pi in the Sky." Check it out from your local public library.

                                    Dan Berger
                                    MadSci Administrator