2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/119305Nonlinear Schrödinger (NLS) equations with focusing power nonlinearities have solitary wave solutions. The spectra of the linearized operators around these solitary waves are intimately connected to stability properties of the solitary waves, and to the long-time dynamics of solutions of (NLS). We study these spectra in detail, both analytically and numerically.submitted December 2005, revised November 2006Analysis of PDEs35Q55, 35P15text