Larry Spruch

TL;DR: In this article, the authors discuss three different mechanisms for the capture of a light particle from a bare heavy nucleus by another bare heavy nuclei which is incident with a very high relative velocity, and a comparison of the relative importance of the different mechanisms in the case of electron capture from hydrogenlike ''atoms''.

TL;DR: In the more than half century since the semiclassical Thomas-Fermi theory of the atom was introduced, there have been literally thousands of publications based on that theory; they encompass a broad range of atomic bound-state and scattering problems as mentioned in this paper.

TL;DR: The quantized surface mode technique is used to evaluate the interaction V of a ``particle'' (an electron or atom) with two sets of plane parallel walls of arbitrary thicknesses and arbitrary permittivities and shows that it can be treated as a single wall with an effective reflection coefficient scrR.

TL;DR: The use of variational principles as a calculational tool is reviewed in this article, with special emphasis on methods for constructing such principles, and it is shown that for a very wide class of problems it is possible to construct a variational principle (VP) for just about any given quantity $Q$ of interest, by routine procedures which do not require the exercise of ingenuity; the resultant VP will yield an estimate of $Q $ correct to second order whenever the quantities appearing in the VP are known to first order.