On lattices of topologies of unary algebras
A unar is an algebra with one unary operation. It is shown that the class of all lattices of topologies of unars is not axiomatizable. Further characterizations of those unars whose lattices of topologies are modular, distributive, complemented, pseudocomplemented, Boolean or chains are given, respectively. In particular, the conditions for modularity and distributivity are equivalent for lattices of topologies of unars.
scientific article; zbMATH DE number 1964710