Fourier Transformations

So what was Fourier’s discovery, and why is it useful? Imagine playing a note on a piano. When you press the piano key, a hammer strikes a string that vibrates to and fro at a certain fixed rate (440 times a second for the A note). As the string vibrates, the air molecules around it bounce to and fro, creating a wave of jiggling air molecules that we call sound. If you could watch the air carry out this periodic dance, you’d discover a smooth, undulating, endlessly repeating curve that’s call...

 Molecules of Water and Air Passed Through Famous People

Take water. It's simple, common, and vital. There are more molecules of water in an eight-ounce cup of the stuff than there are cups of water in all the world's oceans. Every cup that passes through a single person and eventually rejoins the world's water supply holds enough molecules to mix fifteen hundred of them into every other cup of water in the world. No way around it: some of the water you just drank passed through the kidneys of Socrates, Genghis Khan, and Joan of Arc. How about ai...

 Get a Child Addicted to the Real Wonders of the World

It’s easy to get a child addicted to real wonders if you start early enough. Simply point them out—they are all around us—and include a few references to what was once thought to be true. Take thunder. Explain that a bolt of lightning rips through the air, zapping trillions of air molecules with energy hotter than the Sun. Those superheated molecules explode out of the way with a crack! Then the bolt is gone, and all those molecules smash into each other again as they fill in the emptiness it...