2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/29534We consider the Bose-Einstein condensate in a parabolic trap as a macroscopic quantum oscillator and describe, analytically and numerically, its collective modes - a nonlinear generalisation of the (symmetric and antisymmetric) Hermite-Gauss eigenmodes of a harmonic quantum oscillator.4 pages, 2 figures, submitted to the Physical Review Revised version (minor changes)Condensed Mattertext