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arXiv · 1109.2283

On surjectively universal Polish groups

Longyun Ding
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Abstract

A Polish group is surjectively universal if it can be continuously homomorphically mapped onto every Polish group. Making use of a type of new metrics on free groups \cite{DG}, we prove the existence of surjectively universal Polish groups, answering in the positive a question of Kechris. In fact, we give several examples of surjectively universal Polish groups. We find a sufficient condition to guarantee that the new metrics on free groups can be computed directly. We also compare this condition with CLI groups.

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Longyun Ding. 2011-09-11. On surjectively universal Polish groups. https://arxiv.org/abs/1109.2283

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