Celebrating Irrational, Transcendental Pi

25:50 minutes

Some 4,000 years ago, Babylonian and Egyptian scholars calculated the ratio of a circle’s circumference to its diameter—or π—to be 3.125 and 3.1605, respectively. Archimedes later refined their estimations to 3.14163. Today, with the help of computers, scientists have calculated some 10 trillion digits of pi. In our celebration of Pi Day (March 14, or 3.14), mathematician Steven Strogatz talks about how the ancients calculated pi—and how you can do it at home with a box of toothpicks.

Segment Guests

Steven Strogatz

Steven Strogatz is the author of Infinite Powers: How Calculus Reveals the Secrets of the Universe (Houghton Mifflin Harcourt, 2019) and The Joy of X (Eamon Dolan/Houghton Mifflin Harcourt, 2012) and a math professor at Cornell University in Ithaca, New York.

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Christopher Intagliata was Science Friday’s senior producer. He once served as a prop in an optical illusion and speaks passable Ira Flatowese.

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