March 14 has become an annual day of celebration around the world, particularly among those in the technology and engineering communities, as the date is represented by the first three digits of pi (π). This year, pi can be extrapolated to 10 digits – 3.141592653 – on March 14, 2015, at 9:26:53 a.m., making it Super Pi Day.
The Greek letter “π” is a mathematical symbol that represents the ratio of the circumference of a circle to its diameter: if you divide the circumference of any circle by its diameter, you will always get pi (approximately 3.14). However, pi is an irrational number because the digits after the decimal place never end and never repeat. Throughout history, mathematicians have labored to extend the known digits of pi. More recently, some schools have held competitions for students to recite pi to as many digits as they can, with the winner receiving… a pie.
To celebrate the 10 digits represented on Super Pi Day, we thought we’d share 10 notable moments in the history of pi, including a few fun facts about the other pie. Enjoy!
c. 1900–1680 B.C. — Ancient Babylonians recorded the value of pi as 3.125 on a tablet.
c. 1304–1237 B.C.— Bakers to the pharaohs incorporated nuts, honey, and fruits in bread dough, creating a primitive form of pastry. Drawings of this sweet treat can be found etched on the tomb walls of Ramses II, located in the Valley of the Kings in Egypt.
c. 250 B.C. — The ancient Greek mathematician Archimedes documented an algorithm for calculating pi using polygons.
c. 480 A.D. — Zu Chongzhi, a prominent Chinese mathematician and astronomer, calculated the value of pi to 8 decimal places, a level of precision that would be unmatched for nearly 1,000 years.
1430 — In an effort to calculate the circumference of the universe, Persian astronomer and mathematician Jamshid al-Kashi estimated pi to 14 decimal places.
1706 — Mathematicians begin using the Greek letter “π,” replacing approximations such as 22/7, non-standard symbols, and awkward word descriptors like “the quantity which, when the diameter is multiplied by it, yields the circumference.”
1879 — Albert Einstein, one of the world’s great physicists, was born on March 14 in Ulm, Germany.
1880–1910 — Samuel Clemens, better known as Mark Twain, was a big fan of eating pies. His life-long housekeeper and friend often baked huckleberry pie to lure her employer into breaking his habit of skipping lunch.
1949 — The first time a computer was used to calculate pi: the ENIAC (Electronic Numerical Integrator and Computer) was able to determine pi to 2,000 places. The calculation took 70 hours to complete.
2010 — According to Guinness World Records, the world’s largest pumpkin pie was made on September 25. The pie measured 20 feet (6 meters) in diameter and weighed a whopping 3,699 pounds (1,678 kg). Who’s hungry?