Consistent posets

Ivan Chajda; Helmut Länger

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arXiv · 2006.16053

Consistent posets

Ivan Chajda·Helmut Länger

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Abstract

We introduce so-called consistent posets which are bounded posets with an antitone involution ' where the lower cones of x,x' and of y,y' coincide provided x,y are different form 0,1 and, moreover, if x,y are different form 0 then their lower cone is different form 0, too. We show that these posets can be represented by means of commutative meet-directoids with an antitone involution satisfying certain identities and implications. In the case of a finite distributive or strongly modular consistent poset, this poset can be converted into a residuated structure and hence it can serve as an algebraic semantics of a certain non-classical logic with unsharp conjunction and implication. Finally we show that the Dedekind-MacNeille completion of a consistent poset is a consistent lattice, i.e. a bounded lattice with an antitone involution satisfying the above mentioned properties.

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BibTeX RIS

Ivan Chajda, Helmut Länger. 2020-06-26. Consistent posets. https://arxiv.org/abs/2006.16053

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