Incidence algebras of simplicial complexes

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With any locally finite partially ordered set K its incidence algebra Ω(K) is associated. We shall consider algebras over fields with characteristic zero. In this case there is a correspondence K ↔ Ω(K) such that the poset K can be reconstructed from its incidence algebra up to an isomorphism -- due to Stanley theorem. In the meantime, a monotone mapping between two posets in general induces no homomorphism of their incidence algebras. In this paper I show that if the class of posets is confined to simplicial complexes then their incidence algebras acquire the structure of differential moduli and the correspondence K↔Ω(K) is a contravariant functor.