The influence of a small cardinal on the product of a Lindelöf space and the irrationals

Author:
L. Brian Lawrence

Journal:
Proc. Amer. Math. Soc. **110** (1990), 535-542

MSC:
Primary 54B10; Secondary 03E35, 54D20

DOI:
https://doi.org/10.1090/S0002-9939-1990-1021211-4

MathSciNet review:
1021211

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Abstract | References | Similar Articles | Additional Information

Abstract: It is unknown whether there is in ZFC a Lindelöf space whose product with the irrationals is nonnormal. We give some necessary conditions based on the minimum cardinality of unbounded family in .

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Additional Information

DOI:
https://doi.org/10.1090/S0002-9939-1990-1021211-4

Keywords:
Product,
irrationals,
separable completely metrizable space,
Lindelöf space,
normal,
Michael line,
concentrated space,
Continuum Hypothesis,
Martin's axiom

Article copyright:
© Copyright 1990
American Mathematical Society