On Cellular-Compact and related spaces

Angelo Bella

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arXiv · 1910.10445

On Cellular-Compact and related spaces

Angelo Bella

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Abstract

Tkachuk and Wilson proved that a regular first countable cellular-compact space has cardinality not exceeding the continuum. In the same paper they asked if this result continues to hold for Hausdorff spaces. Xuan and Song considered the same notion and asked if every cellular-compact space is weakly Lindelof. We answer the last question for first countable spaces. As a byproduct of this result, we present a somewhat different proof of Tkachuk and Wilson theorem, valid for the wider class of Urysohn spaces. The result actually holds for a class of spaces in between cellular-compact and cellular-Lindelof. We conclude with some comments on the cardinality of a weakly linearly Lindelof space.

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Angelo Bella. 2019-10-23. On Cellular-Compact and related spaces. https://arxiv.org/abs/1910.10445

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