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arXiv · 2104.14048

Characterizing representability by principal congruences for finite distributive lattices with a join-irreducible unit element

George Grätzer
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Abstract

For a finite distributive lattice $D$, let us call $Q \subseteq D$ \emph{principal congruence representable}, if there is a finite lattice $L$ such that the congruence lattice of $L$ is isomorphic to $D$ and the principal congruences of $L$ correspond to $Q$ under this isomorphism. We find a necessary condition for representability by principal congruences and prove that for finite distributive lattices with a join-irreducible unit element this condition is also sufficient.

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George Grätzer. 2021-04-29. Characterizing representability by principal congruences for finite distributive lattices with a join-irreducible unit element. https://arxiv.org/abs/2104.14048

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