2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/90424The time evolution of wave packets in a harmonic oscillator potential is studied. Some new results for the most general case are obtained. A natural number, called ``degree of rigidity'', is introduced to describe qualitatively how much the shape of a wave packet is changed with time. Two classes of wave packets with an arbitrarily given degree of rigidity are presented.REVTeX4, 8 pages, no figureQuantum Physicstext