From Point Vortices to Vortex Patches in Self-Similar Expanding Configurations

The main result is that given a self-similarly expanding configuration of 3 point vortices that start sufficiently far out, we can instead take compactly supported vorticity functions, and the resulting solution to 2D incompressible Euler will evolve like a nearby point vortex configuration for all time, with the size of the patches growing at most as t(1/4+epsilon) and the distance between them growing as root t.