SENSITIVE DEPENDENCE IN CONTROL-SYSTEMS AND REACHABLE SETS

The Key concept of control systems theory is controllability. Often th e ability to find precise control strategies which transfer a state to any other state is too demanding on the system and the lesser require ment of maximal reachability is considered. We develop various reachab ility theorems and show that a local, or truncated, Lyapunov exponent gives a strong indication of reachability.