Optical vortices in nonlinear media: Spirals, forks, and knots

A summary is presented of recent theoretical and experimental results on the dynamics of optical vortices embedded in laser beams propagating in self-focusing nonlinear media. I discuss the spiraling of vortices in nonlocal solitons and elliptic laser beams as well as the pitchfork topological reactions of vortices observed recently in experiments with vortex beams in nematic liquid crystals. Several examples of more exotic structures are presented, such as vortex links and knots, forming spontaneously and under the action of soliton internal modes.