2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/188572We present a generalized equations-of-motion method that efficiently calculates energy spectra and matrix elements for algebraic models. The method is applied to a 5-dimensional quartic oscillator that exhibits a quantum phase transition between vibrational and rotational phases. For certain parameters, 10 by 10 matrices give better results than obtained by diagonalising 1000 by 1000 matrices.4 pages, 1 figureNuclear Theorytext