March 13, 2023

Here’s a fun fact: 3.14, the two-decimal-place value of pi (π), also represents the date March 14, which is Albert Einstein’s birthday. It seems appropriate that the person credited with the greatest insight in math since Isaac Newton would have his birthday represented by an irrational number.

In honor of both pi and Professor Einstein, March 14 is recognized as Pi Day. It began in 1988 when physicist Larry Shaw of San Francisco’s Exploratorium held a circular parade and led a feast of fruit pies. One could say a circular parade is irrational, but then so is pi.

Pi is the ratio of a circle’s circumference to its diameter. Its elusive value has fascinated academics and engineers for millennia, having been approximated by Archimedes in ancient Greece. It needed a name, and was first called “pi” in 1706 by mathematician William Jones, because he noted that pi is the first letter in the Greek word for perimeter, “perimitros.”

The quest to find its value with more precision has led to computing power competition — a Google Cloud calculation in 2022 carried its value out to 100 trillion digits. That’s probably close enough if you need to figure the size of a vent hole in a wall.

Space exploration would not be possible without pi. The National Aeronautics and Space Administration (NASA) recognizes Pi Day and offers teachers a series of “Pi in the Sky” math challenge questions for grades 4-12. The Jet Propulsion Lab holds the NASA Pi Day Challenges for students from kindergarten through the 12th grade, providing classroom material showing how pi is used in determining orbits, surface mapping, asteroid tracking, and much more.

Here at Elite, 100-trillion digit precision is more than we need, but that doesn’t mean it’s less significant. Here’s another fun fact if significant digits are important to you. When your clocks came to 1:59 on March 14, you were three decimal places more precise, since pi to six digits is 3.14159.

Pi is a mathematical feature that has made scientific insights possible through all of recorded history. A circle’s relationship to itself is wonderfully irrational, and so is the language that describes it. That’s why we appreciated circles as we enjoyed some pie on March 14.

*(Images: honorsociety.com, flickr.com)*

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