Dense Sδ-diagonals and linearly ordered extensions


  • Masami Hosobuchi Tokyo Kasei Gakuin University



Sδ-diagonal, Dense Sδ-diagonal, Linearly ordered space (LOTS), Generalized ordered space (GO-space), Linearly ordered extension


The notion of the Sδ-diagonal was introduced by H. R. Bennett to study the quasi-developability of linearly ordered spaces. In an earlier paper, we obtained a characterization of topological spaces with an Sδ-diagonal and we showed that the Sδ-diagonal property is stronger than the quasi-Gδ-diagonal -diagonal property. In this paper, we define a dense Sδ-diagonal of a space and show that two linearly ordered extensions of a generalized ordered space X have dense Sδ-diagonals if the sets of right and left looking points are countable.


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Author Biography

Masami Hosobuchi, Tokyo Kasei Gakuin University

Department of Housing and Planning


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How to Cite

M. Hosobuchi, “Dense Sδ-diagonals and linearly ordered extensions”, Appl. Gen. Topol., vol. 4, no. 1, pp. 71–77, Apr. 2003.



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