2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/28600The Bethe ansatz for the one-dimensional s=1/2 Heisenberg ferromagnet is introduced at an elementary level. The presentation follows Bethe's original work very closely. A detailed description and a complete classification of all two-magnon scattering states and two-magnon bound states are given for finite and infinite chains. The paper is designed as a tutorial for beginning graduate students. It includes 10 problems for further study.8 pages, 4 figuresStatistical Mechanicstext