Structural Chaos

A dynamical system is called "chaotic" if small changes to its initial conditions can create large changes in its behavior. By analogy, call a dynamical system "structurally chaotic" if small changes to the equations describing the evolution of the system produce large changes in its behavior. Although there are many denitions of "chaos", there are few mathematically precise candidate denitions of \structural chaos."  I propose a denition, and I explain two new theorems that show that a set of models is structurally chaotic if contains a chaotic function. I conclude by discussing the relationship between structural chaos and structural stability.