Chaos, as understood by natural scientists, is deterministic or ordered randomness. This leads to some interesting questions: what is randomness? how can something which is random also be ordered? Chaos theory is fundamentally a theory about how well we can know natural phenomena. To determine the orbit of a planet in Newtonian mechanics we must have detailed information about the planet's position and velocity at a certain time. We also must know the positions and velocities of other bodies in the planet's gravitation field. Myriad factors affect the course of a planet. We can only calculate the orbit to the accuracy of our knowledge of all the factors which affect it. The slightest errors in our knowledge prevent us from predicting the exact course of the planet. The deviation of the planet from the calculated orbit is the signature of chaos--a fundamental sensitivity on the part of physical systems to their initial conditions.
From the complexity of large scaled classical phenomena to the curious structure of fractals, Chaos theory allows us to recognize order where before we had only seen disorder.
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