The homology of the Higman–Thompson groups

Markus Szymik1, Nathalie Wahl2
1Department of Mathematical Sciences, NTNU Norwegian University of Science and Technology, Trondheim, Norway
2Department of Mathematical Sciences, University of Copenhagen, Copenhagen, Denmark

Tóm tắt

We prove that Thompson’s group  $$\mathrm {V}$$ is acyclic, answering a 1992 question of Brown in the positive. More generally, we identify the homology of the Higman–Thompson groups  $$\mathrm {V}_{n,r}$$ with the homology of the zeroth component of the infinite loop space of the mod  $$n-1$$ Moore spectrum. As  $$\mathrm {V}=\mathrm {V}_{2,1}$$ , we can deduce that this group is acyclic. Our proof involves establishing homological stability with respect to r, as well as a computation of the algebraic K-theory of the category of finitely generated free Cantor algebras of any type n.

Từ khóa


Tài liệu tham khảo

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