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No uncountable Polish group can be a right-angled Artin group - MaRDI portal

No uncountable Polish group can be a right-angled Artin group (Q2275122)

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No uncountable Polish group can be a right-angled Artin group
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    No uncountable Polish group can be a right-angled Artin group (English)
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    2 October 2019
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    Summary: We prove that if \(G\) is a Polish group and \(A\) a group admitting a system of generators whose associated length function satisfies: (i) if \(0 < k < \omega\), then \(l g(x) \leq l g(x^k)\); (ii) if \(l g(y) < k < \omega\) and \(x^k = y\), then \(x = e\), then there exists a subgroup \(G^\ast\) of \(G\) of size \(\mathfrak{b}\) (the bounding number) such that \(G^\ast\) is not embeddable in \(A\). In particular, we prove that the automorphism group of a countable structure cannot be an uncountable right-angled Artin group. This generalizes analogous results for free and free abelian uncountable groups.
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    descriptive set theory
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    Polish group topologies
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    right-angled Artin groups
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