Ehud Meron

We study the dynamics of vortices that arise in two-dimensional nonequilibrium systems above a Hopf bifurcation to uniform, temporal oscillations. Evolution equations for the vortex positions and for a global phase field are derived and used to study vortex interactions. We suggest that the interactions need not be purely attractive or repulsive; bound vortex pairs can exist, which either precess around fixed points in the plane, or drift in directions perpendicular to the inter-vortex axes.