Title: Morphisms and Duality for Polarities

Speaker: Robert Goldblatt (Victoria University of Wellington)

Time: 2025/09/16 (Tuesday) 15:10-17:10

Location: Room 211, Natural Sciences Teaching Building (理教), Peking University

Abstract:

We review the theory of bounded morphisms and other validity-preserving constructions on Kripke frames, and their role in defining a duality with the class of modal algebras that provide algebraic semantics for modal logics. We then introduce a notion of morphism between structures based on polarities that provide relational semantics for some non-distributive propositional logics, including orthologic, and show how this gives rise to a duality with certain lattice-based algebras.