activity
20242026
collaborators

5 papers

math.GT2026

Cusped spaces for hierarchically hyperbolic groups, and applications to Dehn filling quotients

Giorgio Mangioni, Alessandro Sisto

We introduce a construction that simultaneously yields cusped spaces of relatively hyperbolic groups, and spaces quasi-isometric to Teichmueller metrics. We use this to study Dehn-…

math.GR2025

Random quotients preserve acylindrical and hierarchical hyperbolicity

Carolyn Abbott, Daniel Berlyne, Giorgio Mangioni +2

We propose a new model for random quotients of groups using independent random walks. In this model, we show that random quotients of acylindrical hyperbolic groups asymptotically…

math.GR2024

Short hierarchically hyperbolic groups II: quotients and the Hopf property for Artin groups

Giorgio Mangioni, Alessandro Sisto

We prove that most Artin groups of large and hyperbolic type are Hopfian, meaning that every self-epimorphism is an isomorphism. The class covered by our result is generic, in the…

math.GR2024

Short hierarchically hyperbolic groups I: uncountably many coarse median structures

Giorgio Mangioni

We prove that the mapping class group of a sphere with five punctures admits uncountably many coarsely equivariant coarse median structures. The same is shown for right-angled Arti…

math.GR2024

A combination theorem for hierarchically quasiconvex subgroups, and application to geometric subgroups of mapping class groups

Giorgio Mangioni

We provide sufficient conditions for two subgroups of a hierarchically hyperbolic group to generate an amalgamated free product over their intersection. The result applies in parti…