2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/198194A spin-statistics theorem and a PCT theorem are obtained in the context of the superselection sectors in Quantum Field Theory on a 4-dimensional space-time. Our main assumption is the requirement that the modular groups of the von Neumann algebras of local observables associated with wedge regions act geometrically as pure Lorentz transformations. Such a property, satisfied by the local algebras generated by Wightman fields because of the Bisognano-Wichmann theorem, is regarded as a natural primitive assumption.15 pages, plain TeX, an error in the statement of a theorem has been corrected, to appear in Commun. Math. PhysFunctional AnalysisHigh Energy Physics - TheoryOperator Algebrastext