



























In 1980, U. Faigle introduced a sort of finite geometries on posets that are in bijective correspondence with finite semimodular lattices. His result has almost been forgotten in lattice theory. Here we simplify the axiomatization of these geometries, which we call Faigle geometries. To exemplify their usefulness, we give a short proof of a theorem of Grätzer and E. Knapp (2009) asserting that each slim semimodular lattice $L$ has a congruence-preserving extension to a slim rectangular lattice of the same length as $L$. As another application of Faigle geometries, we give a short proof of G. Grätzer and E. W. Kiss' result from 1986 (also proved by M. Wild in 1993 and the present author and E. T. Schmidt in 2010) that each finite semimodular lattice $L$ has an extension to a geometric lattice of the same length as $L$.
此内容由惯性聚合(RSS阅读器)自动聚合整理,仅供阅读参考。 原文来自 — 版权归原作者所有。