Just-infinite Groups and Topological Full Groups of Minimal Subshifts
نویسنده
چکیده
There does not exist an isomorphism-invariant Borel map which selects a just-infinite quotient of each infinite finitely generated group.
منابع مشابه
Topological Full Groups of Minimal Subshifts and Just-infinite Groups
In [24], confirming a conjecture of Hjorth-Kechris [16], Thomas-Velickovic proved that the isomorphism relation on the space Gfg of finitely generated groups is a universal countable Borel equivalence relation. (Here Gfg denotes the Polish space of finitely generated groups introduced by Grigorchuk [12]; i.e. the elements of Gfg are the isomorphism types of marked groups (G, c ), where G is a f...
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