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arXiv · 1510.05127

Perfect independent sets with respect to infinitely many relations

Martin Doležal·Wiesław Kubiś
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Abstract

We prove a result on perfect cliques with respect to countably many G-delta relations on a complete metric space. As an application, we show that a Polish group contains a free subgroup generated by a perfect set as long as it contains any uncountable free subgroup. This answers a recent question of Głcab and Strobin.

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BibTeXRIS

Martin Doležal, Wiesław Kubiś. 2015-10-17. Perfect independent sets with respect to infinitely many relations. https://arxiv.org/abs/1510.05127

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