Twenty-Five Years of Progress in the Three-Nucleon Problem

Abstract

Twenty-five years ago the International Few-Body Conference was held in Quebec City. It became very clear at that meeting that the theoretical situation concerning the He3 and H3 ground states was confused. A lack of computational power prevented converged brute-force solutions of the Faddeev or Schroedinger equations, both for bound and continuum states of the three-nucleon systems. Pushed by experimental programs at Bates and elsewhere and facilitated by the rapid growth of computational power, converged solutions were finally achieved about a decade later. Twenty-five years ago the first three-nucleon force based on chiral-symmetry considerations was produced. Since then this symmetry has been our guiding principle in constructing three-nucleon forces and, more recently, nucleon-nucleon forces. We are finally nearing an understanding of the common ingredients used in constructing both types of forces. I will discuss these and other issues involving the few-nucleon systems and attempt to define the current state-of-the-art.