Atom structures and Sahlqvist equations
نویسنده
چکیده
This paper addresses the question for which varieties of boolean algebras with operators membership of an atomic algebra A is determined by its atom structure AtA. We prove a positive answer for conjugated Sahlqvist varieties; we also show that the conjugation condition is necessary. As a corollary to the positive result and a recent result by I. Hodkinson, we prove that the variety RRA of representable relation algebras, although canonical, cannot be axiomatised by Sahlqvist equations.
منابع مشابه
Atom Structures of Cylindric Algebras and Relation Algebras
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