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In a profinite group: Does the existence of a countable generating (topologically) set imply the existence of a countable basis for the topology.

Pablo
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1 Answers1

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This depends on what you mean by countably generated. If you mean by a countable set of generators converging to 1 then yes, see the Ribes and Zalesskii book.

If you mean a countable set generating a dense subgroup the answer is no. If you take the free profinite group on a countably infinite discrete space X (not in the converging to 1 sense) then the closure of X is the Stone-Čech compactification of X which is not countably based.