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arXiv · 2311.12599

Ivanova contact join-semilattices are not finitely axiomatizable

Paolo Lipparini
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Abstract

We show that the class of Contact join-semilattices, as introduced by T. Ivanova, is not finitely axiomatizable. On the other hand, a simple finite axiomatization exists for the class of those join semilattices with a weak contact relation which can be embedded into the reduct of a Boolean algebra (equivalently, a distributive lattice) with a weak contact relation.

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Paolo Lipparini. 2023-11-21. Ivanova contact join-semilattices are not finitely axiomatizable. https://doi.org/10.1093/jigpal%2Fjzaf008

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