Scattering solutions of the spinless Salpeter equation

A method to compute the scattering solutions of a spinless Salpeter equation (or a Schrodinger equation) with a central interaction is presented. This method relies on the 3-dimensional Fourier grid Hamiltonian method used to compute bound states. It requires only the evaluation of the potential at equally spaced grid points and yields the radial part of the scattering solution at the same grid points. It can be easily extended to the case of coupled channel equations and to the case of non-local interactions.Comment: 7 page

Comment on "Quantum mechanics of smeared particles"

In a recent article, Sastry has proposed a quantum mechanics of smeared particles. We show that the effects induced by the modification of the Heisenberg algebra, proposed to take into account the delocalization of a particle defined via its Compton wavelength, are important enough to be excluded experimentally.Comment: 2 page

Miscellanea

Miscellane

Recent Manuscript Discoveries

The keeper of the manuscripts in the British Museum, Mr. H. ldris Bell, has announced the more or less recent acquisition, all within the last three years, of still more fragments of Greek papyri relating to the gospels and antedating any of the New Testament manuscripts hitherto known. He described the first of these acquisitions in an article in the London Times of January 23, 1935. Our own American news weekly Time considered this find of new papyri of sufficient newsworthy import to refer to it promptly in its issue of February 4, 1935, and with refreshing accuracy

New Testament Fellowship: A Study in Semantics

In the seventeen passages of the New Testament which employ χοινωνία the associative idea is uppermost. One readily distinguishes three chief usages of the term: 1) a common sharing in all spiritual-and sometimes material-gifts; logically followed by 2) mutual help and assistance by association in contributory aid, all of which affects, and is effected by, 3) the existing intimate fellowship in the association as a divinely created and established communion of all believers in Christ

Miscellanea

Miscellane

How Geometry Controls the Tearing of Adhesive Thin Films on Curved Surfaces

Flaps can be detached from a thin film glued on a solid substrate by tearing and peeling. For flat substrates, it has been shown that these flaps spontaneously narrow and collapse in pointy triangular shapes. Here we show that various shapes, triangular, elliptic, acuminate or spatulate, can be observed for the tears by adjusting the curvature of the substrate. From combined experiments and theoretical models, we show that the flap morphology is governed by simple geometric rules.Comment: 6 pages, 5 figure

Auxiliary field method and analytical solutions of the Schr\"{o}dinger equation with exponential potentials

The auxiliary field method is a new and efficient way to compute approximate analytical eigenenergies and eigenvectors of the Schr\"{o}dinger equation. This method has already been successfully applied to the case of central potentials of power-law and logarithmic forms. In the present work, we show that the Schr\"{o}dinger equation with exponential potentials of the form $-\alpha r^\lambda \exp(-\beta r)$ can also be analytically solved by using the auxiliary field method. Formulae giving the critical heights and the energy levels of these potentials are presented. Special attention is drawn on the Yukawa potential and the pure exponential one