Finitely approximable groups and actions Part I: The Ribes - Zaluesskiĭ property
نویسنده
چکیده
We investigate extensions of S. Solecki’s theorem on closing off finite partial isometries of metric spaces [11] and obtain the following exact equivalence: any action of a discrete group Γ by isometries of a metric space is finitely approximable if and only if any product of finitely generated subgroups of Γ is closed in the profinite topology on Γ. §
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ورودعنوان ژورنال:
- J. Symb. Log.
دوره 76 شماره
صفحات -
تاریخ انتشار 2011