Compact factors in finally compact products of topological spaces

Compact Factors in Finally Compact Products of Topological Spaces

We present instances of the following phenomenon: if a product of topological spaces satisfies some given compactness property then the factors satisfy a stronger compactness property, except possibly for a small number of factors. The first known result of this kind, a consequence of a theorem by A. H. Stone, asserts that if a product is regular and Lindelöf then all but at most countably many...

Products of Nearly Compact Spaces

Products of sequential CLP-compact spaces are CLP-compact

It is shown that the product of finitely many sequential, CLP-compact spaces is CLPcompact. The class of spaces which have the property that every cover by clopen sets — sets which are both open and closed — has a finite subcover was introduced by A. Šostak in [1] under the name CBcompact. These spaces are now known as CLP-compact spaces and their study is linked to the question of whether the ...

Quasi-compact Operators in Topological Linear Spaces

The classical theorems of Riesz [l] on compact operators have been extended by Leray [2] and Williamson [3] to the context of topological linear spaces. Ringrose [4] has shown that if an operator on such a space is compact, the square of its adjoint is also compact, where the topology on the dual space is that of uniform convergence on bounded sets. Thus if an operator is continuous and some po...

Properties of Dμ-Compact Spaces in Generalized Topological Spaces

The aim of this paper is to introduce a further generalization of compactness in generalized topological spaces. We define and study the concept of Dμ-compact spaces in generalized topological spaces. A space(X, μ) is Dμ-compact if every Dμ-cover of X has a finite Dμ-sub cover. Basic properties and characterizations of Dμ-compact space are established. Dμ-compactness in subspaces, products of g...