Infinite games and chain conditions

Santi Spadaro

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arXiv · 1507.02134

Infinite games and chain conditions

Santi Spadaro

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Abstract

We apply the theory of infinite two-person games to two well-known problems in topology: Suslin's Problem and Arhangel'skii's problem on $G_\delta$ covers of compact spaces. More specifically, we prove results of which the following two are special cases: 1) every linearly ordered topological space satisfying the game-theoretic version of the countable chain condition is separable and 2) in every compact space satisfying the game-theoretic version of the weak Lindel\"of property, every cover by $G_\delta$ sets has a continuum-sized subcollection whose union is $G_\delta$-dense.

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Santi Spadaro. 2015-07-08. Infinite games and chain conditions. https://arxiv.org/abs/1507.02134

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