ON FILTER EXPANSION OF TOPOLOGIES

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Published: Mar 1, 1994
DOI: https://doi.org/10.5556/j.tkjm.25.1994.4425
Keywords:
Semiopen and alpha-open sets filter expansion of topologies semi-T0-identification space T_R, R_0,R_1 and semi-R_i, i in {0, 1}

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M. E. ABD EL-MONSEF
Department of Mathematics, Faculty of Science, Tanta University, Tanta, Egypt.
A. M. KOZAE
Department of Mathematics, Faculty of Science, Tanta University, Tanta, Egypt.
A. A. ABO KHAORA
Department of Mathematics, Faculty of Science, Tanta University, Tanta, Egypt.

Abstract




The lower separation axioms $T_i$, ($i \in \{0, 1, 2\}$) are obviously preserved under topology expansions. This fact is not generally valid for higher separation axioms as well as for recent sorts of separation such as $T_R$, $R_0$, $R_1$ and semi-$R_i$, ($i \in \{0, 1\}$). The purpose of the present work is to investigate preservation of these recent separation properties under filter expansion of topologies. Also, we study the effect of filter expansions on the concept $s$-essentially $T_i$- spaces, ($i \in \{0, 1\}$).




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How to Cite
EL-MONSEF, M. E. A., KOZAE, A. M. ., & KHAORA, A. A. A. (1994). ON FILTER EXPANSION OF TOPOLOGIES. Tamkang Journal of Mathematics, 25(1), 53–59. https://doi.org/10.5556/j.tkjm.25.1994.4425
Issue
Vol. 25 No. 1 (1994)
Section
Papers
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