Oleksandr Maslyuchenko , Vadym Myronyk , Roman Ivasiuk
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引用次数: 0
摘要
我们考虑了空间 S(X×Y,Z)上的两个自然拓扑,S(X×Y,Z)是定义在两个拓扑空间 X 和 Y 的乘积上的所有独立连续函数,并被置换到一个拓扑或度量空间 Z 中。我们证明,如果 X 和 Y 是伪紧凑且 Z 是度量空间,这些拓扑就会重合。我们证明,对于无限紧凑的 X、Y 和可元空间 Z⊇R,当且仅当 K 的权重小于 X 和 Y 两个空间的锐胞度时,紧凑空间 K 嵌入到 S(X×Y,Z)中。
Compact subspaces of the space of separately continuous functions with the cross-uniform topology
We consider two natural topologies on the space of all separately continuous functions defined on the product of two topological spaces X and Y and ranged into a topological or metric space Z. These topologies are the cross-open topology and the cross-uniform topology. We show that these topologies coincides if X and Y are pseudocompacts and Z is a metric space. We prove that a compact space K embeds into for infinite compacts X, Y and a metrizable space if and only if the weight of K is less than the sharp cellularity of both spaces X and Y.
期刊介绍:
Topology and its Applications is primarily concerned with publishing original research papers of moderate length. However, a limited number of carefully selected survey or expository papers are also included. The mathematical focus of the journal is that suggested by the title: Research in Topology. It is felt that it is inadvisable to attempt a definitive description of topology as understood for this journal. Certainly the subject includes the algebraic, general, geometric, and set-theoretic facets of topology as well as areas of interactions between topology and other mathematical disciplines, e.g. topological algebra, topological dynamics, functional analysis, category theory. Since the roles of various aspects of topology continue to change, the non-specific delineation of topics serves to reflect the current state of research in topology.
At regular intervals, the journal publishes a section entitled Open Problems in Topology, edited by J. van Mill and G.M. Reed. This is a status report on the 1100 problems listed in the book of the same name published by North-Holland in 1990, edited by van Mill and Reed.