## Kolmogorov Entropy

Also known as Metric Entropy. Divide Phase Space into -dimensional Hypercubes of Content . Let be the probability that a trajectory is in Hypercube at , at , at , etc. Then define

 (1)

where is the information needed to predict which Hypercube the trajectory will be in at given trajectories up to . The Kolmogorov entropy is then defined by
 (2)

The Kolmogorov entropy is related to Lyapunov Characteristic Exponents by
 (3)