Mathematica Bohemica, Vol. 145, No. 2, pp. 177-190, 2020


$T_2$ and $T_3$ objects at $p$ in the category of proximity spaces

Muammer Kula, Samed Özkan

Received December 27, 2017.   Published online June 12, 2019.

Abstract:  In previous papers, various notions of pre-Hausdorff, Hausdorff and regular objects at a point $p$ in a topological category were introduced and compared. The main objective of this paper is to characterize each of these notions of pre-Hausdorff, Hausdorff and regular objects locally in the category of proximity spaces. Furthermore, the relationships that arise among the various ${\rm Pre}T_2$, $T_i$, $i=0,1,2,3$, structures at a point $p$ are investigated. Finally, we examine the relationships between the generalized separation properties and the separation properties at a point $p$ in this category.
Keywords:  topological category; proximity space; Hausdorff space; regular space
Classification MSC:  54B30, 54E05, 54D10, 18B99


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Affiliations:   Muammer Kula, Erciyes University, Köşk Mahallesi, Talas Blv., 38030 Melikgazi/Kayseri, Turkey, e-mail: kulam@erciyes.edu.tr; Samed Özkan, Nevşehir Haci Bektaş Veli University, 2000 Evler Mahallesi, Zübeyde Hanim Cd., 50300 Merkez/Nevşehir, Turkey, e-mail: ozkans@nevsehir.edu.tr


 
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