Two classes of Fréchet-Urysohn spaces

Author:
Alan Dow

Journal:
Proc. Amer. Math. Soc. **108** (1990), 241-247

MSC:
Primary 54E35; Secondary 03E35, 03E75, 54A35

DOI:
https://doi.org/10.1090/S0002-9939-1990-0975638-7

MathSciNet review:
975638

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Abstract: Arhangel'skii introduced five classes of spaces, -spaces , which are important in the study of products of Fréchet-Urysohn spaces. For each , each -space is an -space and it follows from the continuum hypothesis that there are countable -spaces which are not -spaces. A -space (-space) is a Fréchet-Urysohn -space ( -space). We show that there is a model of set theory in which each -space (-space) is an -space (-space).

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1990-0975638-7

Keywords:
Fréchet-Urysohn space,
-space,
-space

Article copyright:
© Copyright 1990
American Mathematical Society