Congruences and Trajectories in Planar Semimodular Lattices

A 1955 result of J. Jakubík states that for the prime intervals p and q of a finite lattice, con(p) ≥ con(q) iff p is congruence-projective to q (via intervals of arbitrary size). The problem is how to determine whether con(p) ≥ con(q) involving only prime intervals. Two recent papers approached thi...

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Bibliographic Details
Main Author: Grätzer G.
Format: Article
Language:English
Published: Sciendo 2018-06-01
Series:Discussiones Mathematicae - General Algebra and Applications
Subjects:
Online Access:https://doi.org/10.7151/dmgaa.1280
Description
Summary:A 1955 result of J. Jakubík states that for the prime intervals p and q of a finite lattice, con(p) ≥ con(q) iff p is congruence-projective to q (via intervals of arbitrary size). The problem is how to determine whether con(p) ≥ con(q) involving only prime intervals. Two recent papers approached this problem in different ways. G. Czédli’s used trajectories for slim rectangular lattices-a special subclass of slim, planar, semimodular lattices. I used the concept of prime-projectivity for arbitrary finite lattices. In this note I show how my approach can be used to reprove Czédli’s result and generalize it to arbitrary slim, planar, semimodular lattices.
ISSN:2084-0373