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arXiv · 2408.16162

Every Polish group has a non-trivial topological group automorphism

Carlos Pérez Estrada·Ulises Ariet Ramos-García
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Abstract

We prove that every Polish group with more than two elements admits a non-trivial topological group automorphism. As a consequence, a hypothetical uniquely homogeneous Polish space with more than two points cannot be a semitopological group.

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Carlos Pérez Estrada, Ulises Ariet Ramos-García. 2024-08-28. Every Polish group has a non-trivial topological group automorphism. https://arxiv.org/abs/2408.16162

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