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Related papers: Products of two sober dcpo's need not be sober

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In this paper, we mainly investigate the conditions under which the Scott topology on the product of two posets is equal to the product of the individual Scott topologies and under which the Scott topology on a dcpo is sober. Some such…

General Topology · Mathematics 2022-11-29 Xiaoquan Xu

The study of the sobriety of Scott spaces has got an relative long history in domain theory. Lawson and Hoffmann independently proved that the Scott space of every continuous directed complete poset (usually called domain) is sober.…

General Topology · Mathematics 2022-05-03 Hualin Miao , Xiaoyong Xi , Qingguo Li , Dongsheng Zhao

In this paper, we investigate the sobriety of weakly first-countable spaces and give some sufficient conditions that the Scott topologies of the open set lattices are sober. The main results are: (1) Let $P$ and $Q$ be two posets. If…

General Topology · Mathematics 2025-04-09 Zhengmao He

In this paper, we mainly discuss some basic properties of Scott power spaces. For a $T_0$ space $X$, let $\mathsf{K}(X)$ be the poset of all nonempty compact saturated subsets of $X$ endowed with the Smyth order. It is proved that the Scott…

General Topology · Mathematics 2022-07-19 Xiaoquan Xu , Xinpeng Wen , Xiaoyong Xi

By Thron, a topological space $X$ has the property that $C(X)$ isomorphic to $C(Y)$ implies $X$ is homeomorphic to $Y$ iff $X$ is sober and $T_D$, where $C(X)$ and $C(Y)$ denote the lattices of closed sets of $X$ and $T_0$ space $Y$,…

General Topology · Mathematics 2016-07-14 Dongsheng Zhao , Luoshan Xu

We construct a complete lattice $Z$ such that the binary supremum function $\sup:Z\times Z\to Z$ is discontinuous with respect to the product topology on $Z\times Z$ of the Scott topologies on each copy of $Z$. In addition, we show that…

Logic in Computer Science · Computer Science 2016-07-15 Peter Hertling

M. Escard\'o et al. asked whether the core compactly generated topology of a sober space is again sober and the sobrification of a core compactly generated space again core compactly generated. In this note, we answer the problem by…

General Topology · Mathematics 2023-05-02 Qingguo Li , Hualin Miao

With a complete residuated lattice $L$ as the truth value table, we extend the definition of sobriety of classical convex spaces to the framework of $L$-convex spaces. We provide a specific construction for the sobrification of an…

General Topology · Mathematics 2024-08-19 Guojun Wu , Wei Yao

We prove that (1) for any complete lattice $L$, the set $\mathcal{D}(L)$ of all nonempty saturated compact subsets of the Scott space of $L$ is a complete Heyting algebra (with the reverse inclusion order); and (2) if the Scott space of a…

General Topology · Mathematics 2019-03-05 Xiaoquan Xu , Xiaoyong Xi , Dongsheng Zhao

We introduce and study a new class of $T_0$ spaces, called open well-filtered spaces. The main results we proved include (1) every well-filtered space is an open well-filtered space; (2) every core-compact open well-filtered space is sober.…

General Topology · Mathematics 2023-06-22 Chong Shen , Xiaoyong Xi , Xiaoquan Xu , Dongsheng Zhao

It is proved that a metric space is sober, as an approach space, if and only if it is Smyth complete.

General Topology · Mathematics 2017-06-20 Wei Li , Dexue Zhang

The Hofmann-Mislove theorem states that in a sober space, the nonempty Scott open filters of its open set lattice correspond bijectively to its compacts saturated sets. In this paper, the concept of $c$-well-filtered spaces is introduced.…

General Topology · Mathematics 2023-06-22 Liping Zhang , Xiangnan Zhou , Qingguo Li

The collection of all topologies on a set X forms a complete lattice with respect to the inclusion order, which have been investigated by many researchers. Sobriety is one of the core and extensively studied properties in non-Hausdorff…

General Topology · Mathematics 2025-08-08 Xiangrui Li , Qingguo Li , Dongsheng Zhao

We define a class of subsets of a topological space that coincides with the class of compact saturated subsets when the space is sober, and with enough good properties when the space is not sober. This class is introduced especially in view…

General Topology · Mathematics 2011-06-21 Paul Poncet

A metric space X is straight if for each finite cover of X by closed sets, and for each real valued function f on X, if f is uniformly continuous on each set of the cover, then f is uniformly continuous on the whole of X. A locally…

General Topology · Mathematics 2008-10-01 Alessandro Berarducci , Dikran Dikranjan , Jan Pelant

In analogy to a result due to Drake and Thron about topological spaces, this paper studies the dcpos (directed complete posets) which are fully determined, among all dcpos, by their lattices of all Scott-closed subsets (such dcpos will be…

General Topology · Mathematics 2023-06-22 Dongsheng Zhao , Luoshan Xu

Let $X$ be a complete $\mathbb{Q}$-factorial toric variety. We explicitly describe the space $H^2(X,T_X)$ and the cup product map $H^1(X,T_X)\times H^1(X,T_X)\to H^2(X,T_X)$ in combinatorial terms. Using this, we give an example of a smooth…

Algebraic Geometry · Mathematics 2020-06-24 Nathan Ilten , Charles Turo

In this paper, we highlight some open problems stated by Xu and Zhao. In particular, we focus on strong $d$-spaces and answer two open problems concerning strong $d$-spaces. One is about the product space of an arbitrary family of strong…

General Topology · Mathematics 2021-09-24 Mengjie Jin , Hualin Miao , Qingguo Li

In this paper, we provide a uniform approach to $d$-spaces, sober spaces and well-filtered spaces, and develop a general framework for dealing with all these spaces. For a subset system H, the theory of H-sober spaces and super H-sober…

General Topology · Mathematics 2020-03-18 Xiaoquan Xu

The Ho-Zhao problem asks whether any two dcpo's with isomorphic Scott closed set lattices are themselves isomorphic, that is, whether the category $\mathbf{DCPO}$ of dcpo's and Scott-continuous maps is $\Gamma$-faithful. In 2018, Ho,…

Logic in Computer Science · Computer Science 2024-09-04 Hualin Miao , Huijun Hou , Xiaodong Jia , Qingguo Li
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