Volvox carteri is a hollow green ball about the width of a pinhead, made of roughly two thousand cells. Each of them has two flagella, and they beat in coordination, so the whole sphere rolls as it swims. Held inside, suspended in jelly, are about sixteen much larger cells. These have no flagella. They do […]
Right now, without any sound, galaxies are leaving. Not moving away in the ordinary sense — not flying off through space like debris from a blast. Space itself is expanding, everywhere at once, and at great distances the expansion adds up to more than light can cross. A galaxy far enough away is carried from […]
A waterfall has a shape. Go back to the same one after a year and you will recognize it — the same white curl where the water folds over the lip, the same standing wave below, the same plume of mist hung in the same place in the air. You could photograph it, name it, […]
Pour milk into coffee. The white blooms, curls, slackens, drowns into an even brown. Now run the film backward. The brown unmixes. The milk gathers itself and leaps into the jug. Everyone laughs. No one can say which law was broken. None was. Every single collision in that cup is reversible — run any one […]