2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/113801Assuming the continuum hypothesis, we prove that B(H) has a pure state whose restriction to any masa is not pure. This resolves negatively an old conjecture of Anderson.3 pagesOperator AlgebrasFunctional AnalysisLogic46A32; 46L30; 47L05 ; 03E50Not all pure states on B(H) are diagonalizabletext