Automorphism groups of universal diversities

Andreas Hallbäck

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arXiv · 2004.11798

Automorphism groups of universal diversities

Andreas Hallbäck

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Abstract

We prove that the automorphism group of the Urysohn diversity is a universal Polish group. Furthermore we show that the automorphism group of the rational Urysohn diversity has ample generics, a dense conjugacy class and that it embeds densely into the automorphism group of the (full) Urysohn diversity. It follows that this latter group also has a dense conjugacy class.

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Andreas Hallbäck. 2020-04-24. Automorphism groups of universal diversities. https://arxiv.org/abs/2004.11798

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