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arXiv · 1903.08041

Countably compact groups and sequential order

Dmitri Shakhmatov·Alexander Shibakov
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Abstract

We use $\diamondsuit$ to construct, for every $\alpha\leq\omega_1$ a sequential countably compact topological group of sequential order $\alpha$. This establishes the independence of the existence of sequential countably compact non Fr\'echet groups from the usual axioms of ZFC and answers several questions of D.~Shakhmatov.

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Dmitri Shakhmatov, Alexander Shibakov. 2019-03-19. Countably compact groups and sequential order. https://arxiv.org/abs/1903.08041

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