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arXiv · 2501.08298

Q-Sets, \Delta-Sets, and L-Spaces

Pourya Memarpanahi·Paul Szeptycki
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Abstract

The question whether there is a Lindelof Q-set space or Lindelof $\Delta$-set space is considered. We show that J. Moore's ZFC $L$-space is not a Q-set space in ZFC and, assuming all Aronszajn trees are special, it is not a $\Delta$-set space.

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Pourya Memarpanahi, Paul Szeptycki. 2025-01-14. Q-Sets, \Delta-Sets, and L-Spaces. https://arxiv.org/abs/2501.08298

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