Sam P. Fisher

activity

20222026

most citedThe Hanna Neumann Conjecture for graphs of free groups with cyclic edge groups

1 citations · 1 across the 8 of their papers we have counts for

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math.GR2024

Dimension drop in residual chains

Sam P Fisher, Kevin Klinge

We give a description of the Linnell division ring of a countable residually (poly- $Z$ virtually nilpotent) (RPVN) group in terms of a generalised Novikov ring, and show th…

math.GR2024

On the cohomological dimension of kernels of maps to $Z$

Sam P. Fisher

We prove that if $G$ is a finitely generated RFRS group of cohomological dimension $2$ , then $G$ is virtually free-by-cyclic if and only if $b_{2}^{(2)} (G) = 0$ . This answers a quest…

Dimension drop in residual chains

On the cohomological dimension of kernels of maps to Z

On the cohomological dimension of kernels of maps to $Z$