“…A nonlocal equation is characterized by integral operators acting on a lengthscale or "horizon", describing long-range forces and reducing the regularity requirements on the solutions. Engineering applications include surface or subsurface transport [3,4,21,30,31,47,48], fracture mechanics [29,34,52], turbulence [32,41], image processing [1,11,27,35] and stochastic processes [6,13,37,39,40].…”