Abstract:
A generalized Baumslag–Solitar group (a $GBS$ group) is a finitely generated group $G$ acting on a tree so that all vertex and edge stabilizers are infinite cyclic groups. Each $GBS$ group is the fundamental group $\pi_1(\mathbb A)$ of some labeled graph $\mathbb A$. We describe the centralizers of elements and the centralizer lattice. Also, we find the centralizer dimension for $GBS$ groups if $\mathbb A$ is a labeled tree.