✦ LIBER ✦

Selectors and scattered spaces

✍ Scribed by G. Artico; U. Marconi; R. Moresco; J. Pelant

Publisher: Elsevier Science
Year: 2001
Tongue: English
Weight: 130 KB
Volume: 111
Category: Article
ISSN: 0166-8641
DOI: 10.1016/s0166-8641(99)00193-5

No coin nor oath required. For personal study only.

✦ Synopsis

Selectors on F(X) are studied. Non-Archimedean P -spaces with a continuous selector are shown to be precisely scattered spaces (or topologically well-orderable ones). Several results are given for spaces with a unique accumulation point p; e.g., if the filter of its neighborhoods (without p) is a sum two free ultrafilters then the existence of a continuous selector for all such spaces is equivalent to the non-existence of a measurable cardinal.

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