In 1690, the Dutch physicist Christiaan Huygens published a slim volume in French titled Traité de la Lumière. In it, he proposed something radical: that light is not a stream of particles, as Isaac Newton believed, but a wave that propagates through space like ripples through water. The scientific establishment,…

In the history of mathematics, few disputes have been as bitter or as consequential as the fight over calculus. Isaac Newton developed his “method of fluxions” in the mid-1660s while hiding from the plague in Woolsthorpe. Gottfried Wilhelm Leibniz, working independently in Paris a decade later, arrived at the same…

On December 21, 1968, three men sat atop 6.2 million pounds of thrust and waited for someone to light the fuse. Frank Borman, Jim Lovell, and Bill Anders were about to do something no human being had ever done. They were going to leave Earth orbit, travel a quarter of…

Quick: what do you know about Fibonacci? If you are like most people, you know one thing: the Fibonacci sequence, that pattern where each number is the sum of the two before it. 1, 1, 2, 3, 5, 8, 13, 21, and so on. It shows up in sunflower heads…

Here is a fact that should keep you up at night: the most important scientific book ever written almost did not get published. Not because it was controversial (though it was). Not because the author lost the manuscript (though that happened too, sort of). It almost did not get published…

In 1790, France was tearing itself apart. The monarchy was crumbling, mobs filled the streets of Paris, and the National Assembly was busy reinventing every institution in the country. And somewhere in the middle of all this chaos, a group of scientists received one of the strangest assignments in history:…

Somewhere beyond the edge of our solar system, traveling at roughly 17 kilometers per second, a gold-plated copper disc is carrying the sound of a human heartbeat into interstellar space. It has been traveling since 1977. It will keep traveling for billions of years. Long after Earth’s continents have rearranged…

On a December evening in 1935, Irene Joliot-Curie stood before the Nobel Committee in Stockholm to accept the Prize in Chemistry. She was thirty-eight years old. Twenty-four years earlier, her mother had stood in the same city, accepting her second Nobel Prize. No other mother and daughter have ever both…

In 1807, a French mathematician walked into the Institut de France in Paris and made a claim so bold that the most distinguished scientists of the age refused to believe it. Joseph Fourier told them that any function (any curve, no matter how irregular, how jagged, how seemingly chaotic) could…

Every time you buy something online, log into your bank account, or send an encrypted message, you are relying on a mathematical truth that a Greek scholar proved around 300 BCE. Euclid of Alexandria demonstrated that there are infinitely many prime numbers. He could never have imagined that this elegant…