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aura拓扑空间中的紧性和连通性

Compactness and Connectedness in Aura Topological Spaces

Balikesir University(巴勒基谢尔大学)

Ahu Acikgoz

AI总结:

本文研究了aura拓扑空间中的紧性和连通性,定义了多种紧性类型及其关系,并探讨了连通性的相关性质。

摘要:

本文是关于aura拓扑空间$(X, τ, \mathfrak{a})$系列论文的第二篇,其中$\mathfrak{a}: X → τ$是一个范围函数,满足$x ∈ \mathfrak{a}(x)$。我们研究了在此设定下的覆盖和连通性质。定义了五种紧性类型($\mathfrak{a}$-紧、$\mathfrak{a}$- Lindelof、可数$\mathfrak{a}$-紧、$\mathfrak{a}$-序列紧、$\mathfrak{a}$-极限点紧)及其相互关系。对于传递的aura函数,我们得到一个具体的收敛准则:$(x_n)$在$τ_{\mathfrak{a}}$中收敛到$x$当且仅当$x_n ∈ \mathfrak{a}(x)$最终成立。我们证明了$\mathfrak{a}$-紧子集在$\mathfrak{a}$-$T_2$空间中是$\mathfrak{a}$-闭的,并且$\mathfrak{a}$-紧性在$\mathfrak{a}$-连续满射下保持不变。在连通性方面,引入了$\mathfrak{a}$-连通、$\mathfrak{a}$-路径连通和$\mathfrak{a}$-局部连通空间;$\mathfrak{a}$-成分是$\mathfrak{a}$-闭的,当空间是$\mathfrak{a}$-局部连通时,它们也是$\mathfrak{a}$-开的。我们构建了子空间和乘积aura拓扑。对于乘积,建立了包含链$(τ_{\mathfrak{a}}) × (τ_{\mathfrak{b}}) ⊆ τ_{\mathfrak{a} × \mathfrak{b}} ⊆ τ_X × τ_Y$,当两个范围函数都是传递时,左边的包含是等号。证明了对于传递的aura空间的Tychonoff型定理。所有蕴含都被反例证明为严格成立。

英文摘要:

This is the second paper in a series on aura topological spaces $(X, τ, \mathfrak{a})$, where $\mathfrak{a}: X \to τ$ is a scope function with $x \in \mathfrak{a}(x)$. We study covering and connectivity properties in this setting. Five compactness-type notions are defined ($\mathfrak{a}$-compact, $\mathfrak{a}$-Lindelof, countably $\mathfrak{a}$-compact, $\mathfrak{a}$-sequentially compact, $\mathfrak{a}$-limit point compact) and their mutual relationships are determined. For transitive aura functions we obtain a concrete convergence criterion: $(x_n)$ converges to $x$ in $τ_{\mathfrak{a}}$ if and only if $x_n \in \mathfrak{a}(x)$ eventually. We show that $\mathfrak{a}$-compact subsets of $\mathfrak{a}$-$T_2$ spaces are $\mathfrak{a}$-closed and that $\mathfrak{a}$-compactness is preserved under $\mathfrak{a}$-continuous surjections. On the connectivity side, $\mathfrak{a}$-connected, $\mathfrak{a}$-path connected, and $\mathfrak{a}$-locally connected spaces are introduced; $\mathfrak{a}$-components are $\mathfrak{a}$-closed, and they are $\mathfrak{a}$-open when the space is $\mathfrak{a}$-locally connected. We construct subspace and product aura topologies. For products the inclusion chain $(τ_{\mathfrak{a}}) \times (τ_{\mathfrak{b}}) \subseteq τ_{\mathfrak{a} \times \mathfrak{b}} \subseteq τ_X \times τ_Y$ is established, with equality on the left when both scope functions are transitive. A Tychonoff-type theorem for transitive aura spaces is proved. All implications are shown to be strict by counterexamples.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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