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arXiv · 2203.03734

On the LS-category of homomorphisms

Alexander Dranishnikov·Nursultan Kuanyshov
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Abstract

We prove the equality $\cat(ϕ)=\cd(ϕ)$ for homomorphisms $ϕ:Γ\to Λ$ of a torsion free finitely generated nilpotent groups $Γ$ to an arbitrary group $Λ$. We construct an epimorphism $ψ:G\to H$ between geometrically finite groups with $\cat(ψ)> \cd(ψ)$.

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Alexander Dranishnikov, Nursultan Kuanyshov. 2022-03-07. On the LS-category of homomorphisms. https://arxiv.org/abs/2203.03734

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