Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas ( IF 2.9 ) Pub Date : 2021-03-26 , DOI: 10.1007/s13398-021-01029-z J. C. Ferrando , J. Ka̧kol , W. Śliwa
An internal characterization of the Arkhangel’skiĭ-Calbrix main theorem from [4] is obtained by showing that the space \(C_{p}(X)\) of continuous real-valued functions on a Tychonoff space X is K-analytic framed in \(\mathbb {R}^{X}\) if and only if X admits a nice framing. This applies to show that a metrizable (or cosmic) space X is \(\sigma \) -compact if and only if X has a nice framing. We analyse a few concepts which are useful while studying nice framings. For example, a class of Tychonoff spaces X containing strictly Lindelöf Čech-complete spaces is introduced for which a variant of Arkhangel’skiĭ-Calbrix theorem for \(\sigma \)-boundedness of X is shown.
中文翻译:
空间$$ C_ {p}(X)$$ C p(X)的有界分辨率和以X表示的特征
通过显示Tychonoff空间X上连续实值函数的空间\(C_ {p}(X)\)是K-解析框架而获得的,来自[4]的Arkhangel'skiĭ-Calbrix主定理的内部表征当且仅当X接受好框架时,才在\(\ mathbb {R} ^ {X} \)中。这适用于表明,当且仅当X具有良好的框架时,可量化(或宇宙)的空间X是\(\ sigma \)-紧凑的。我们分析了一些在研究框架时有用的概念。例如,一类Tychonoff空间X引入了严格包含LindelöfČech完全空间的空间,针对该空间,显示了X的\(\ sigma \)有界的Arkhangel'skiĭ-Calbrix定理的一个变体。