Pi Day

March 14, 2021 – Adrianna Holt, Adult Services

So what’s the big deal about pi? 

Pi is the ratio between the circumference of a circle and its diameter. There is so much more to pi than that though!  If you’ve ever taken a math course that involves this mathematical concept, then you very well know that it is an irrational, transcendental number, it continues on to infinity…and beyond! However, when it is involved in problem-solving it is abbreviated to the first three digits (3.14) or the fraction 22/7, these are frequently approved as accurate estimations. Since 2019, pi has been calculated to more than 31.4 trillion decimal places and I doubt that mathematicians are going to stop there. 

The person that is first and foremost commonly credited for being able to accurately calculate the estimated value of pi is the ancient Greek mathematician Archimedes. The Egyptians and Babylonians by the year 2000 BC were accurately using pi to build stuff. Mathematicians such as Fibonacci, François Viète, Gottfried Wilhelm Leibniz, and Adriaan van Roomenall calculated pi by various methods. 

The first celebration of Pi Day was founded in 1988 by Lawrence N. Sha, an American physicist, curator, artist and founder of Pi Day. He organized a large-scale celebration at the San Francisco Exploratorium (which the Exploratorium still celebrates to this day) and he chose this day because it obviously represents the first three digits of pi and coincidentally is Albert Einstein’s birthday. Pi Day has become quite trendy in the last decade or so, but it became official on March 12th, 2009, when the U.S. House of Representatives established a non-binding resolution that acknowledged March 14th is National Pi Day. 

Why does pi look like 2 T’s smushed together?

Well, in the 18th century it began to be represented by the Greek letter π. The word, “pi”, is actually derived from the first letter of the Greek word perimetros, which means circumference. This idea was introduced by William Jones in 1706.

How can you celebrate?

In 2015, Pi Day fanatics had a special treat. Celebrations took place on 3/14/15 at 9:26:53 a.m., the numerical date and time together representing the first 10 digits of pi, 3.141592653

You can celebrate this day in a few ways. Like any day, it is up to you how you celebrate! Here are a few ideas:

– Eat any assortment of pie, whether sweet or savory, or perhaps you’ll take a trip to St. Louis and eat at Pi Pizzeria.
– Watch (or read!) Life of Pi.
– Look for deals on March 14th, such as electronics, geeky shirts, and of course, PIZZA.

Want to read about pi and/or pies?

Here are 3 books about PI…

    1. Easy as Pi: The Countless Ways We Use Numbers Every Day by Jamie Buchan 
    2. How to Bake Pi: An Edible Exploration of the Mathematics of Mathematics by Eugenia Cheng 
    3. Humble Pi: When Math Goes Wrong in the Real World by Matt Parker 


…and 14 about PIE: 

    1. Pieometry by Lauren Ko
    2. Mrs. Rowe’s Little Book of Southern Pies by Mollie Cox Bryan 
    3. Pie Squared by Cathy Barrow 
    4. Pie Pie Pie by John Phillip Carroll 
    5. Pie It Forward by Gesine Bullock-Prado 
    6. Art of the Pie by Kate McDermott 
    7. 175 Best Mini Pie Recipes: Sweet to Savory by Julie Anne Hession 
    8. Easy as Pie by Anne Van Wagner Childs
    9. Sweety Pies by Patty Pinner 
    10. Southern Pies by Nancie McDermott 
    11. How to Build a Better Pie by Millicent Souris 
    12. Pie Pops by Marcie Ballard
    13. Magpie by Holly Riccardi 
    14. A Few Good Pie Places (DVD)


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