doing math with strogatz


Let’s begin with what our bodies can teach us. We all know that toddlers learn to count with their fingers and sometimes their toes. Those appendages are called “digits,” and it’s no accident that the same word refers to the 10 symbols 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 in the decimal system. Our bodies are our first arithmetic teachers. But what is less widely known is that our bodies are also trying to teach us higher math, if only we’d let them. Look at a baby’s first hairdo: The cowlick at the center of that cute little swirl is, in mathematical parlance, a “singularity,” a point of confusion where the baby’s hair can’t seem to decide which way to grow. On the back of the cowlick the hair falls to the left; on the front it grows to the right; and on the sides it falls forward and backward. What makes a cowlick “singular” is that a variable (the hair’s direction) changes abruptly and discontinuously there.

more from Steven Strogatz at The Opinionater here.