SELECTION, STABILITY AND RENORMALIZATION

We illustrate how to extend the concept of structural stability throug h applying it to the front propagation speed selection problem. This c onsideration leads us to a renormalization group study of the problem. The study illustrates two very general conclusions: (1) singular pert urbations in applied mathematics are best understood as renormalized p erturbation methods, and (2) amplitude equations are renormalization g roup equations.