[HTML][HTML] Failure of the Blok–Esakia Theorem in the monadic setting

G Bezhanishvili, L Carai - Annals of Pure and Applied Logic, 2025 - Elsevier
Abstract The Blok–Esakia Theorem establishes that the lattice of superintuitionistic logics is
isomorphic to the lattice of extensions of Grzegorczyk's logic. We prove that the Blok–Esakia …

The monadic Grzegorczyk logic

G Bezhanishvili, M Khan - arxiv preprint arxiv:2412.10854, 2024 - arxiv.org
We develop a semantic criterion for determining whether a given monadic modal logic
axiomatizes the one-variable fragment of a predicate modal logic. We show that the criterion …