${\Omega \choose T}\neq {\Omega \choose \Gamma}$

Dominic van der Zypen

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arXiv · 2509.00032

${\Omega \choose T}\neq {\Omega \choose \Gamma}$

Dominic van der Zypen

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Abstract

We show that the selection principles ${\Omega\choose T}$ and ${\Omega\choose\Gamma}$ are not equal constructing a topological space $(X,\tau)$ that satisfies ${\Omega \choose T}$, but not ${\Omega \choose \Gamma}$. This answers a question from arXiv:math/0301011 .

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Dominic van der Zypen. 2025-08-21. ${\Omega \choose T}\neq {\Omega \choose \Gamma}$. https://arxiv.org/abs/2509.00032

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