Strong well-filteredness of upper topology on sup-complete posets

Xiaoquan Xu; Yi Yang; Lizi Chen

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arXiv · 2512.10599

Strong well-filteredness of upper topology on sup-complete posets

Xiaoquan Xu·Yi Yang·Lizi Chen

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Abstract

We first introduce and investigate a new class of $T_0$ spaces -- strong R-spaces, which are stronger than both R-spaces and strongly well-filtered spaces. It is proved that any sup-complete poset equipped with the upper topology is a strong R-space and the Hoare power space of a $T_0$-space is a strong R-space. Hence the upper topology on a sup-complete poset is strongly well-filtered and the Hoare power space of a $T_0$-space is strongly well-filtered, which answers two problems recently posed by Xu.

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BibTeX RIS

Xiaoquan Xu, Yi Yang, Lizi Chen. 2025-12-11. Strong well-filteredness of upper topology on sup-complete posets. https://arxiv.org/abs/2512.10599

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