Most of us first hear about the irrational number π (pi) – rounded off as 3.14, with an infinite number of decimal digits – in school, where we learn about its use in the context of a circle. More ...

For more than a century, Srinivasa Ramanujan’s uncanny formulas for the number pi have looked like pure mathematical fireworks, dazzling but detached from the physical world. Now a new wave of ...