Hausdorff Fréchet closure spaces with maximum topological defect
Ghiloni, Riccardo
Bollettino dell'Unione Matematica Italiana, Tome 5-A (2002), p. 641-665 / Harvested from Biblioteca Digitale Italiana di Matematica
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It is well-known that the topological defect of every Fréchet closure space is less than or equal to the first uncountable ordinal number ω1. In the case of Hausdorff Fréchet closure spaces we obtain some general conditions sufficient so that the topological defect is exactly ω1. Some classical and recent results are deduced from our criterion.

È noto che il difetto topologico di ogni spazio di chiusura di Fréchet é minore o uguale al primo ordinale non numerabile ω1. Nel caso di spazi di chiusura di Hausdorff Fréchet si ottengono alcune condizioni generali sufficienti affinché il difetto topologico sia pari a ω1. Alcuni risultati classici e recenti sono dedotti dal nostro criterio.

Publié le : 2002-10-01
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     author = {Riccardo Ghiloni},
     title = {Hausdorff Fr\'echet closure spaces with maximum topological defect},
     journal = {Bollettino dell'Unione Matematica Italiana},
     volume = {5-A},
     year = {2002},
     pages = {641-665},
     zbl = {1098.54510},
     mrnumber = {1934372},
     language = {en},
     url = {http://dml.mathdoc.fr/item/BUMI_2002_8_5B_3_641_0}
}

Ghiloni, Riccardo. Hausdorff Fréchet closure spaces with maximum topological defect. Bollettino dell'Unione Matematica Italiana, Tome 5-A (2002) pp. 641-665. http://gdmltest.u-ga.fr/item/BUMI_2002_8_5B_3_641_0/

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