2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/59079The main result of this paper is that every (separated) toric variety which has a semigroup structure compatible with multiplication on the underlying torus is necessarily affine. In the course of proving this statement, we also give a proof of the fact that every separated toric variety may be constructed from a certain fan in a Euclidean space. To our best knowledge, this proof differs essentially from the ones which can be found in the literature.LaTeX, 13 pagesAlgebraic Geometrytext