4 papers
The isomorphism problem for random generalized Baumslag-Solitar groups with many edges
Dario Ascari, Alessandra Caraceni
The isomorphism problem for generalized Baumslag-Solitar (GBS) groups is a long-standing open problem. We prove that, in the random model considered here, a GBS graph with many edg…
On the isomorphism problem for generalized Baumslag-Solitar groups: angles
Dario Ascari, Montserrat Casals-Ruiz, Ilya Kazachkov
We introduce a new isomorphism invariant for generalized Baumslag-Solitar (GBS) groups, which we call the limit angle. Unlike previously known invariants, which are primarily algeb…
On the isomorphism problem for generalized Baumslag-Solitar groups: invariants and flexible configurations
Dario Ascari, Montserrat Casals-Ruiz, Ilya Kazachkov
We prove that the isomorphism problem is decidable for generalized Baumslag-Solitar (GBS) groups with one quasi-conjugacy class and full support gaps. In order to do so we introduc…
On the isomorphism problem for cyclic JSJ decompositions: vertex elimination
Dario Ascari, Montserrat Casals-Ruiz, Ilya Kazachkov
We introduce two new moves on graphs of groups with cyclic edge groups that preserve the fundamental group. These moves allow us to address the isomorphism problem without the use…