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arXiv · 1405.6356

Nonexistence of Countable Extremally Disconnected Groups with Many Open Subgroups

Ol'ga Sipacheva
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Abstract

It is proved that the existence of a countable extremally disconnected Boolean topological group containing a family of open subgroups whose intersection has empty interior implies the existence of a rapid ultrafilter.

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Ol'ga Sipacheva. 2014-05-25. Nonexistence of Countable Extremally Disconnected Groups with Many Open Subgroups. https://arxiv.org/abs/1405.6356

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