Skip to main content

What’s in a pi?

Written on |

March 14h is International Pi Day. Why do we celebrate it? Is pi still relevant 4,000 years after being discovered? And is peach pie better than cherry?

What’s the best kind of pie? And what’s the perfect crust-to-filling ratio? Mankind has been struggling with these questions since the dawn of baked goods, which is probably about as long as the number pi has been known to us.

Although Pi Day was first celebrated in the 1980s, the number pi (represented as the Greek letter π) was first discovered about 4,000 years ago. The ratio of a circle’s circumference to the circle’s diameter, pi is always the same, whether you’re measuring a penny or a truck tire. Not only that, but pi is an “irrational” number – no matter how many digits of pi we calculate, we’ll never be able to predict which digit comes next. 

We decided to ask Ofir Gorodetsy, a PhD student at the School of Mathematical Sciences at Tel Aviv University, about the significance of pi.

“The decimal expansion of π starts with 3.14,” Ofir said. “Which is why we celebrate Pi Day on March 14th every year. And aside from being known to Ancient Egyptians and Babylonians, pi is also mentioned in the Hebrew Bible, where the approximation 3 is used to measure the circumference of a circle.”

Too much pi?

Although most people are familiar with pi as being 3.14, mathematicians have been struggling to find the other digits of pi for centuries. According to Ofir, “figuring out the digits of pi gets pretty difficult after a dozen or so. Many scholars from all over the world have tried to find more and more digits: Archimedes, Liu Hui, Brahmagupta, Fibonacci, Isaac Newton. In the 18th century a mathematician even came up with proof that the digits of pi don’t follow any pattern, so they never repeat in any predictable way.”

According to Ofir, figuring out the digits of pi is much easier these days. Even freshmen at university can calculate as many digits as they’d like, using modern tools.

But the magic of pi is not only its length, but how common it is in the natural world. The disk of the sun, the pupil of our eyes, the ripples in a pond, even the way rivers tend to bend and flow can be described using pi. It’s used in the work of biologists, engineers, geographers, physicsts, mathematicians. Almost every discipline that deals with the world around us crosses paths with this unique number at some point. 

So why do we celebrate Pi Day? Probably because math is at its most delicious when it’s fresh out of the oven.

Related posts

Could Restarting Change the Game for Chemical Research?

17 March 2024

Could Restarting Change the Game for Chemical Research?

12 February 2024

New Findings About the Early Universe 50 Million Years After the Big Bang

19 December 2023

Sam Altman to Visit Tel Aviv University

31 May 2023

Plants Emit Sounds – Especially When Stressed

1 April 2023

Munich Philharmonic Names Lahav Shani its Next Chief Conductor

27 February 2023

First Satellite Observatory for Quantum Optical Communication in Israel

16 February 2023

Does a Food Sharing Economy Benefit the Environment?

14 February 2023

Researchers Characterize Earliest Galaxies in the Universe

4 December 2022

The Thinnest Possible Ladder

21 November 2022

TAU Students Team Wins 1st Place in Int’l Mathematics Competition

12 September 2022

Can Music Help Prevent Severe Cognitive Decline?

1 September 2022

New Perspectives on Tackling Human Trafficking

28 July 2022

Impressive achievement for Tel Aviv University in the Bar Association Exam

17 July 2022

Research based on a comprehensive study of 8,000 birds in Israel

9 April 2022

TAU Welcomes Ukrainian Emergency Fellowship Students

1 April 2022


Tok Corporate Centre, Level 1,
459 Toorak Road, Toorak VIC 3142
Phone: +61 3 9296 2065
Email: [email protected]

New South Wales

Level 22, Westfield Tower 2, 101 Grafton Street, Bondi Junction NSW 2022
Phone: +61 418 465 556
Email: [email protected]

Western Australia

P O Box 36, Claremont,
WA  6010
Phone: :+61 411 223 550
Email: [email protected]