Reopening of the conjecture about the decidability of Quasi-Dense Modal Logics (Comments on Lyon & Ostropolski-Nalewaja's result)

2025/07/15 by Olivier Gasquet, Gasquet, Olivier · 1 citation
Computer Science · #Advanced Algebra and Logic #Logic, Reasoning, and Knowledge #Formal Methods in Verification

paper · pdf · doi:10.48550/arxiv.2507.11644

Abstract

In \citeLyon24 the question of the decidability of quasi-dense modal logics is answered, and an upper bound in \EXPSPACE is given. Unfortunately, authors' intricate proof seems to contain a major flaw that cannot be fixed, leaving the question wide open.

Citations

• Decidability of Quasi-Dense Modal Logics
• The core of a graph

Cited by

• PSPACE-completeness of bimodal transitive weak-density logic

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