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This is Science Friday.

I'm Ira Plato.

Today on the podcast, it's why we dedicate a whole day to celebrating pie.

And I mean, the math kind.

You know, our world is filled with periodic, repetitive behavior, and as soon as you try to

describe any of that with math, pie is going to pop up.

Today is March 14th, of course, that's 314 Pi Day, the day of the year where we celebrate the

ratio that makes a circle, a circle. Now, if you think about it, that Greek letter is so part of our

culture that it merits our irrational attention. And here to help slice into our pies and why

they matter so much is Dr. Steven Strogatz, Professor of Math at Cornell University and co-hosts of

Quantum Magazine's podcast, The Joy of Why. Steve, welcome back to Science Friday. Always good to have you.

Thanks so much, Ira. I'm always

really happy to talk to you, thrilled to be here. All right. So you like to talk about the joy of

why. So why pie? Why does this number, this concept, have its own special day? Why is it so

important? It's important in geometry, as we all know from what you mentioned about circles. But I like to

think that the real importance has to do with what circles represent, which is they represent

anything that goes around and around and repeats itself. So think of your heartbeat. Think of the

cycles in the seasons of the year, the orbits of

the planets. You know, our world is filled with periodic, repetitive behavior. And as soon as

you try to describe any of that with math, pie is going to pop up. All right. I'm glad you're brought

up the idea of describing it with math. Because when you talk about pie, the 3.14, what's an easy way to visualize why it's 3.14?

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