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arXiv · 2512.16039

On the finiteness properties of fixed subgroups of automorphisms

Kisnney Almeida·Luis Mendonça
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Abstract

We use Sigma-invariants to study homotopical and homological finiteness properties of fixed subgroups of automorphisms of a group $G$ in terms of its center $Z(G)$ and the induced automorphisms on its associated quotient $G/Z(G)$. Specializing to the case where the center is a direct factor of the group, we answer a question made by Lei, Ma and Zhang.

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Kisnney Almeida, Luis Mendonça. 2025-12-17. On the finiteness properties of fixed subgroups of automorphisms. https://arxiv.org/abs/2512.16039

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