Nonconvex landscapes for ${\mathbf{Z}}_2$ synchronization and graph clustering are benign near exact recovery thresholds

Andrew D. McRae, Pedro Abdalla, Afonso S. Bandeira +1

We study the optimization landscape of a smooth nonconvex program arising from synchronization over the two-element group ${\mathbf{Z}}_2$, that is, recovering $z_1, \dots, z_n \in \…