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arXiv · 1607.04688

On the definability of Menger spaces which are not /sigma-compact

Franklin D. Tall·Secil Tokgoz
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Abstract

Hurewicz proved completely metrizable Menger spaces are /sigma-compact. We extend this to Cech-complete Menger spaces and consistently to projective Menger metrizable spaces. On the other hand, it is consistent that there is a co-analytic Menger space that is not /sigma-compact.

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Franklin D. Tall, Secil Tokgoz. 2016-07-16. On the definability of Menger spaces which are not /sigma-compact. https://arxiv.org/abs/1607.04688

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