Guided Dynamical Systems and Applications to Functional and Partial   Differential Equations
  In this thesis we introduce the concept of a guided dynamical system, and exploit this idea to solve various problems in functional equations and PDE's. Our main results are 1) a necessary and sufficient condition for unique-solvability of an initial value functional equation, 2) a proof of the overdeterminedness of a large class of functional equations and 3) a necessary and sufficient condition for unique-solvability of a boundary value problem for a third order, hyperbolic PDE. 
Orr Shalit