Duality for Constructive Modal Logics: from Sahqlvist to Goldblatt-Thomason
Logic
2026-04-14 v2 Logic in Computer Science
Abstract
We carry out a semantic study of the constructive modal logic CK. We provide a categorical duality linking the algebraic and birelational semantics of the logic. We then use this to prove Sahlqvist style correspondence and completeness results, as well as a Goldblatt-Thomason style theorem on definability of classes of frames.
Keywords
Cite
@article{arxiv.2601.03762,
title = {Duality for Constructive Modal Logics: from Sahqlvist to Goldblatt-Thomason},
author = {Jim de Groot and Ian Shillito and Ranald Clouston},
journal= {arXiv preprint arXiv:2601.03762},
year = {2026}
}