In this episode of The Mathematicians Podcast, host Benjamin Cornish paddles upstream—literally and figuratively—to explore the remarkable life and ideas of Eratosthenes of Cyrene, the polymath who measured the Earth with astonishing precision and devised one of the most famous algorithms in history: the Sieve of Eratosthenes.

In the show today

• How Eratosthenes measured Earth’s circumference over 2,000 years ago

• The ingenious method behind the Sieve of Eratosthenes and why it still matters in modern computing

• His groundbreaking work in geography, including latitude, longitude, and early ideas of a spherical Earth

• His role as chief librarian at the Library of Alexandria—aka the Google of the ancient world

From ancient geometry to prime numbers and historical timekeeping, this episode is a celebration of interdisciplinary thinking, curiosity, and mathematical creativity. Whether you're a teacher, student, or just a curious mind, you'll come away with a renewed appreciation for how math shapes our understanding of the world.

Plus: Learn how to get involved with Un-Natural Numbers, a new YouTube maths chat show supporting emerging voices in math communication.

https://docs.google.com/forms/d/e/1FAIpQLSfve_tIM3e9jh5b_kzIPICmRViIXIcBJ38DyQ5YwfBLzNMHKg/viewform?usp=sharing&ouid=108012955586926932884

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