On the G-compactifications of the rational numbers
نویسنده
چکیده
We show that for any sufficiently homogeneous metrizable compactum X there is a Polish group G acting continuously on the space of rational numbersQ such that X is its unique G-compactification. This allows us to answer Problem 995 in the ‘Open Problems in Topology II’ book in the negative: there is a one-dimensional Polish groupG acting transitively onQ forwhich theHilbert cube is its uniqueG-completion.
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