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Pi Day: Google Employee Breaks Calculation Record – and Other Pi Stories

Pi, Pi Day, Pi symbol, Mathematics Building at the Technical University of Berlin
In celebration of Pi Day, Google has announced one of its employees – Emma Haruka Iwao – has earned a place in the Guinness World Records.

Pi, Pi Day, Pi symbol, Mathematics Building at the Technical University of Berlin

The Pi symbol is represented in a mosaic outside the Mathematics Building at the Technical University of Berlin. (Source: Technical University of Berlin)

Today Google announced that its employee, Emma Haruka Iwao, has calculated Pi out to 31.4 trillion. The Guinness World Records certified Iwao’s calculation on Wednesday. The record makes her the third woman to set a world record for calculating Pi. The previous world record was set by Peter Trueb in 2016 with 24.6 trillion.

Pi, Pi Day, Google, Guinness World Records

Emma Haruka Iwao, a Japan-based developer advocate with Google, set a world record for the longest calculation of Pi, reaching more than 31 trillion decimal places. (Source: Google)

Welcome to Pi Day. March 14 – or 3/14 – signifies Pi, which is the mathematical constant that bears out the relationship between a circle’s circumference and it diameter. It is also called Archimedes Constant. Pi is an irrational number, never settling into a repeating pattern.

The symbol for Pi comes from the lowercase Greek letter that is the first letter of the Greek word perimetros, meaning circumference.

The Roots of Pi Day

1988 is the earliest known official or large-scale celebration of Pi Day. The event was organized by Larry Shaw at the San Francisco Exploratorium where Shaw worked as a physicist. Shaw, the Exploratorium staff, and a few Pi fans, marched around one of its circular spaces while consuming fruit pies. The Exploratorium continues to hold Pi Day celebrations each year on March 14.

On March 12, 2009, the U.S. House of Representatives passed a non-binding resolution (111 H. Res. 224) that recognizes March 14, 2009 as National Pi Day.

There is also a Pi Approximation Day is observed on July 22 (22/7 in the day/month format), since the fraction ​22⁄7 is a common approximation of π, which is accurate to two decimal places and dates from Archimedes.

Interestingly, March 14 is also the birthday of Albert Einstein. Many tech universities – including Massachusetts Institute of Technology and Princeton – hold celebrations to honor both Pi and Einstein. The main feature of the celebrations – of course – is the consumption if pie.

Odd Facts about Pi

According to the Guinness World Records, the record for the most digits of Pi memorized goes to Rajveer Meena of Vellore, India, who recited 70,000 decimal places of Pi on March 21, 2015. Previously, Chao Lu of China held the record set in 2005 for reciting Pi from memory to 67,890 places.

The Great Pyramid at Giza seems to approximate Pi. The vertical height of the pyramid has the same relationship to the perimeter of its base as the radius of a circle has to its circumference.

During the O.J. Simpson trial, defense attorney Robert Blasier questioned an FBI agent about the actual value of Pi. He was trying to discredit the agent based on the agent’s faulty understanding of Pi.

And finally, what do you get if you divide the circumference of a jack-o'-lantern by its diameter? Pumpkin Pi.

Rob Spiegel has covered automation and control for 19 years, 17 of them for Design News. Other topics he has covered include supply chain technology, alternative energy, and cyber security. For 10 years, he was owner and publisher of the food magazine Chile Pepper.

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