Sam P. Fisher

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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.GR2026

A note on normal generation and the first $ℓ^{2}$ -betti number

Sam P. Fisher, Yash Lodha

In $2011$ , Osin and Thom conjectured that the first $ℓ^{2}$ -Betti number of a torsion-free discrete group is bounded above by the normal rank of the group minus one. The conjectur…

math.GR2026

On the top-dimensional $L^{2}$ -Betti number of residually poly- $Z$ groups

Sam P. Fisher, Pablo Sánchez-Peralta

Let $G$ be a residually poly- $Z$ group of finite type. We prove that $G$ admits a poly- $Z$ quotient with kernel $N$ satisfying $\mathrm{cd}_{\mathbb Q}(N) < \mathbb…

A note on normal generation and the first ℓ2-betti number

On the top-dimensional L2-Betti number of residually poly-Z groups

A note on normal generation and the first $ℓ^{2}$ -betti number

On the top-dimensional $L^{2}$ -Betti number of residually poly- $Z$ groups