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arXiv · 1503.03919

An example of a non non-archimedean Polish group with ample generics

Maciej Malicki
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Abstract

For an analytic $P$-ideal $I$, $S_I$ is the Polish group of all the permutations of $\mathbb{N}$ whose support is in $I$, with Polish topology given by the corresponding submeasure on $I$. We show that if $\mbox{Fin} \subsetneq I$, then $S_I$ has ample generics. This implies that there exists a non non-archimedean Polish group with ample generics.

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Maciej Malicki. 2015-03-13. An example of a non non-archimedean Polish group with ample generics. https://arxiv.org/abs/1503.03919

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