Low‐energy electron‐atom and electron‐molecule scattering theory circa 1964

Let me begin with the remark that, to avoid continual reiteration of an awkward phrase, I shall simply say “electron scattering” where it is obvious that I am referring to electron‐atom and/or electron‐molecule collisions, which collisions may be elastic or inelastic. Progress in electron‐scattering theory has been reviewed on numerous occasions in recent years, by various authors. Thus, there is not much point in trying to re‐review in detail here the whole subject of electron scattering, especially since I couldn't possibly do it within the pages of this entire issue of Physics Today. Instead, I shall confine my attention largely to topics wherein what has been happening within the past two years or so seems important. By important, I mean that—to me at least—these happenings suggest modifications of apparently established points of view. Even with this very severe restriction on the subjects I intend to discuss, I really can't do justice to the available material in an article of this length. A reasonable idea of the feverish present activity in the field of electron scattering, as well as a notion of the breadth of topics falling under this general subject heading, can be obtained from thumbing through the Proceedings of the Third International Conference on the Physics of Electronic and Atomic Collisions.