Mappings on weakly Lindelöf and weakly regular-Lindel¨of spaces

Anwar Jabor Fawakhreh; Adem Kiliçman

doi:10.4995/agt.2011.1647

Authors

Anwar Jabor Fawakhreh Qassim University
Adem Kiliçman University Putra Malaysia

DOI:

https://doi.org/10.4995/agt.2011.1647

Keywords:

Lindelöf, weakly Lindelöf and weakly regular-Lindel¨of space, Almost continuous and almost precontinuous functions

Abstract

In this paper we study the effect of mappings and some decompositions of continuity on weakly Lindelöf spaces and weakly regular-Lindelöf spaces. We show that some mappings preserve these topological properties. We also show that the image of a weakly Lindelöf space (resp. weakly regular-Lindelöf space) under an almost continuous mapping is weakly Lindelöf (resp. weakly regular-Lindelöf). Moreover, the image of a weakly regular-Lindelöf space under a precontinuous and contracontinuousmapping is Lindelöf.

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Author Biographies

Anwar Jabor Fawakhreh, Qassim University

Department of Mathematics, Collage of Science, Qassim University, P.O. Box 6644, Buraydah 51402, Saudi Arabia.

Adem Kiliçman, University Putra Malaysia

Department of Mathematics and Institute for Mathematical Research, University Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia

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