Projectively universal countable metrizable groups

Vladimir G. Pestov; Vladimir V. Uspenskij

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arXiv · 1409.4108

Projectively universal countable metrizable groups

Vladimir G. Pestov·Vladimir V. Uspenskij

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Abstract

We prove that there exists a countable metrizable topological group $G$ such that every countable metrizable group is isomorphic to a quotient of $G$. The completion $H$ of $G$ is a Polish group such that every Polish group is isomorphic to a quotient of $H$.

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Vladimir G. Pestov, Vladimir V. Uspenskij. 2014-09-14. Projectively universal countable metrizable groups. https://arxiv.org/abs/1409.4108

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