IS NOTHING sacred? Even the idle weekend pastime of skimming stones on a lake has been taken apart and reduced to a mathematical formula.
Everyone knows a stone bounces best on water if it’s round and flat, and spun towards the water as fast as possible. Some enthusiasts even travel to international stone-skimming competitions, like world champion Jerdone Coleman-McGhee, who made a stone bounce 38 times on Blanco River, Texas, in 1992.
Intuitively, a flat stone works best because a relatively large part of its surface strikes the water, so there’s more bounce. Inspired by his eight-year-old son, physicist LydĂ©ric…


