J. Hillman

collaborators

2 papers

math.GT2021

Nilpotent groups with balanced presentations. II

J. A. Hillman

If $G$ is a nilpotent group with a balanced presentation and $G \neq ≅ Z^{3}$ then $β_{1} (G; Q) \leq 2$ \cite{Hi22}. We show that if such a group $G$ has an abelian nor…

math.GT2021

Subnormality in $P D_{3}$ -groups and $L^{2}$ -Betti numbers

J. A. Hillman

We reconsider work of Elkalla on subnormal subgroups of 3-manifold groups, giving essentially algebraic arguments that extend to the case of $P D_{3}$ -groups and group pairs. However…

Nilpotent groups with balanced presentations. II

Subnormality in PD3​-groups and L2-Betti numbers

Subnormality in $P D_{3}$ -groups and $L^{2}$ -Betti numbers