J. Hillman

collaborators

3 papers

math.GT2026

$P D_{4}$ -complexes with $I ¨ _{2}$ a projective $Z [I ¨ _{1}]$ -module

Jonathan A. Hillman

Let $X$ be a $P D_{4}$ -complex and let $I ¨ = I ¨ _{1} (X)$ . If $I ¨ $ is torsion-free and $I ¨ _{2} (X)$ is a finitely generated projective $Z [I ¨ ]$ -module then either $I ¨ $ is free or $I ¨ $ …

math.GT2026

Aspherical $P D_{3}$ -pairs

Jonathan A. Hillman

We extend two results known for aspherical 3-manifolds to $P D_{3}$ -pairs $(P, \partial P)$ with aspherical ambient space $P$ . Every such $P D_{3}$ -pair may be assembled by attaching 1-h…

math.GT2026

On sections of Lefschetz fibrations and bundles over 2-complexes

Jonathan A. Hillman, Riccardo Pedrotti

We address the question of existence of sections of fibrations in two settings. First, we show that a bundle with base a finite 2-complex admits a section if and only if the inclus…

PD4​-complexes with I¨2​ a projective Z[I¨1​]-module

Aspherical PD3​-pairs

On sections of Lefschetz fibrations and bundles over 2-complexes

$P D_{4}$ -complexes with $I ¨ _{2}$ a projective $Z [I ¨ _{1}]$ -module

Aspherical $P D_{3}$ -pairs