A Ladder Operator Solution to the Particle in a Box Problem

A ladder operator solution to the particle in a box problem of elementary quantum mechanics is presented, although the pedagogical use of this method for this problem is questioned.

Compact Singlet S Helium Wave functions(corrected)

This is a corrected version of the Phys. Rev. A 74,14501 (2006) article. The result is improved slightly from that in the original paper.

The Wave Equation for Stringed Instruments

An elementary derivation of the wave equation as applied to violin strings is given.