Results about the Alexandroff duplicate space


  • Khulod Almontashery King Abdulaziz University
  • Lutfi Kalantan King Abdulaziz University



Alexandroff duplicate, normal, almst normal, mildly normal, quasi-normal, pseudo compact, Property $\omega D$, $\alpha$-normal, epinormal.


In this paper, we present some new results about the  Alexandroff Duplicate Space. We prove that if a space X has the property P, then its Alexandroff Duplicate space A(X) may not have P, where P is one of the following properties: extremally disconnected, weakly extremally disconnected, quasi-normal, pseudo compact. We prove that if X is $\alpha$-normal, epinormal, or has property $\omega D$, then so is A(X). We prove almost normality is preserved by A(X) under special conditions.


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Author Biographies

Khulod Almontashery, King Abdulaziz University

Department of Mathematics

Lutfi Kalantan, King Abdulaziz University

Department of Mathematics


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How to Cite

K. Almontashery and L. Kalantan, “Results about the Alexandroff duplicate space”, Appl. Gen. Topol., vol. 17, no. 2, pp. 117–122, Oct. 2016.