Algodoo

Chaos theory demo using double pendulums

All of the pendulums in this demo which look similar have been made using the Clone command, so each pendulum in each group is "identical".

However, the pendulums on the left start with enough energy to display chaotic motion, so small differences in their initial position and the calculations as they change (ie, rounding errors) get magnified, so that the pendulums swing along increasingly different paths.

The single pendulums on the right do not display chaotic behaviour, so small differences stay very small, so they remain indistinguishable. The double pendulums at the bottom right do not have enough energy to get into the chaotic region.