2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/143070Following (and elaborating on) a method of Logan and van Luijk, we exhibit explicit genus-2 curves whose Jacobians have nontrivial 2-torsion in their Tate-Shafarevich groups.17 pages, comments welcomeNumber TheoryAlgebraic Geometrytext