Skip to main content
3 of 3
Commonmark migration

A topology on $\Bbb R$ where the compact sets are precisely the countable sets

QUESTION.

In there a topology on $\Bbb R$ where the compact subsets are precisely the countable subsets?

I am trying to create a counterexample to a certain claim, and I found that what I need is a topology of this kind. I thought hard about this and did quite a lot of searching, but could not find something relevant. Thank you in advance.

Note: "countable" includes "finite".

Cauchy
  • 233
  • 1
  • 6