Tag Archives: forbidden substructures

Characterizing non-ω-well-filtered spaces by forbidden subspaces

Posted on February 20, 2026 by jgl

In a 2023 paper, Hualin Miao, Xiaodong Jia, Chong Shen and Qingguo Li characterized ω-well-filtered spaces as those that do not contain any one of two very simple spaces, S1 and SD, as Skula-closed subspaces. This is part of a … Continue reading →

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All countable continuous dcpos are algebraic

Posted on May 20, 2025 by jgl

A little pearl this month: as the title says, all countable continuous dcpos are algebraic. Read the full post.

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Forbidden substructures

Posted on March 19, 2018 by jgl

Characterizing properties of graphs, posets, and even dcpos by forbidden substructures is an intriguing approach.  Xiaodong Jia managed to show that every CCC of quasi-continuous domains must consist of continuous domains exclusively, and I would like to explain how this rests … Continue reading →

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