Another closure operator on preneighbourhood spaces

Document Type : Research Paper

Author

Department of Mathematical Sciences, University of South Africa, Unisa Science Campus, corner of Christiaan de Wet & Pioneer Avenue, Florida 1709, Johannesburg, Gauteng, South Africa.\\ National Institute for Theoretical and Computational Sciences (NITheCS), South Africa.

Abstract

The notions of dense, proper, separated or perfect morphisms and hence of compact, Hausdorff or compact Hausdorff are all consequent to good properties of a family of closed morphisms is well known in literature. Deeper consequences like the Tychonoff product theorem or the Stone Čech compactifications follow from richer properties of the set of closed morphisms. The purpose of this paper is to provide a closure operation on a preneighbourhood space so that the resulting set of closed morphisms possess all the properties mentioned above. 

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