Happy Pi Day!

One of the most endearing and enduring qualities of humans is that we're so often sure that we can find the answer to any problem if we just try hard enough. For 3,500years, humankind has attempted to solve the puzzle of pi, also called "squaring the circle", calculating the exact ratio of a circle's circumference to its diameter. However, no matter how hard anyone tries, they find only a new approximation.

In ancient Greece, the great mathematician Archimedes worked tirelessly to discover the ratio, uncovering only a few digits of accuracy. When he tried to stop a Roman soldier from blundering over his work by shouting "do not touch my circles" he was unceremoniously murdered.


Pi is in art

By the time Ludolf van Ceulen died in 1610, he had spent many years of his life tediously calculating pi, resulting in only 35 accurate digits. And in 1873, William Shanks announced he had found 707 digits over years of hand-cramping work; unfortunately, he had made a mistake after the 527th place. The following digits were all wrong.

The most recent attempt, by a Japanese computer scientist in 2002, found 1.24 trillion digits of pi. To put all this in perspective, even an astrophysicist, attempting to measure galaxies, would never need more than 10 or 15 digits of precision. But pi beckons us on further. Some mathematicians believe that if we could only find some pattern in pi, even some hint that there were more fours than sevens, it could lead to a huge breakthrough in our understanding of the universe.

Pi shows up everywhere. In mathematics, pi appears in many fundamental equations that have nothing to do with circles. In science, pi is inextricable from measuring everything from ocean waves to economic statistics.

Pi is found in the very measurements of the Great Pyramid at Giza. And if you divide the length of a river from source to mouth across a gently sloping plane by its direct length "as the crow flies", you'll find pi.

Pi also appears where you least expect it. Religious scholars point to the Old Testament which, when describing the measurements of Solomon's Temple, implies that pi is only three. In the transcripts of the famed OJ Simpson trial, you can find arguments between the judge and an FBI agent about the actual value of pi.