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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 $ a{ \leq ^*}$ unbounded family in $ {}^\omega \omega $.


References [Enhancements On Off] (What's this?)

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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

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