← All simulators

Shapes and chance

Order and Chaos

Four experiments where order appears, or never does, on its own, drawn in 3D and held to the physics by tests. The waterwheel is Malkus's continuous wheel, whose equations the tests show are Lorenz's to a billionth: with the tap low it stops, medium it spins steadily at the rate Lorenz gives, high it reverses again and again at no regular interval, and two wheels a billionth apart soon turn opposite ways. The metronomes are Lagrange's equations for five pendulums on a board that rolls, with a clockwork kick: the tests see momentum kept with no clockwork, and five seeds falling into step on the rolling board and not on a fixed table. The pendulum wave is fifteen exact pendulums cut to swing 51 to 65 times a minute, tested back in line at 60 s and in two rows at 30 s. The jar is a discrete element simulation of 281 glass balls: the tests hold a bounce to its restitution and a still pile to staying still, and see the big ball climb from under about 260 balls to under fewer than 60 when shaken at 2 g, and stay put when not. Ours: every size, mass and setting, and the metronomes' clockwork.