2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/17585Convergent expansions of the wavefunctions for the ground state and low-lying excited states of quantum transverse Ising systems are obtained. These expansions are employed to prove that the dispersion relation for a single quasi-particle has a convergent expansion.22 pagesStatistical MechanicsMathematical Physicstext