Cracking Eggs 101

[S]cience has finally come up with an explanation for what comes naturally to most home cooks: Eggs crack best around their equators, says MIT mechanical engineer Pedro Reis, because of their geometry. He and a young colleague, Arnaud Lazarus, have just published a paper in Physical Review Letters demonstrating a link between an eggshell’s geometry (it belongs to a class of shapes known as ovoids) and a mechanical property called rigidity—the quality that, along with strength, determines how much force an object can withstand before it cracks.