Closure algebras of depth two with extremal relations: Their frames, logics, and structural completeness

2023/09/19 by Düntsch, Ivo, Dzik, Wojciech
#03B45 #FOS: Mathematics #Logic (math.LO)

paper · doi:10.48550/arxiv.2309.10946

Abstract

We consider varieties generated by finite closure algebras whose canonical relations have two levels, and whose restriction to a level is an "extremal" relation, i.e. the identity or the universal relation. The corresponding logics have frames of depth two, in which a level consists of a set of simple clusters or of one cluster with one or more elements.

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