In physics and mathematics, in the area of dynamical systems, a double pendulum is a pendulum with another pendulum attached to its end, is a simple physical system that exhibits rich dynamic behavior with a strong sensitivity to initial conditions.[1] The motion of a double pendulum is governed by a set of coupled ordinary differential equations and is chaotic. A double pendulum released from a small initial angle behaves similarly to the single pendulum. On the other hand, releasing it from a large enough initial angle will produce chaotic behaviour which is impossible to predict. Why are double pendulums so chaotic? A double pendulum executes simple harmonic motion (two normal modes) when displacements from equilibrium are small. However, when large displacements are imposed, the non-linear system becomes dramatically chaotic in its motion and demonstrates that deterministic systems are not necessarily predictable

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