Global results for the inhomogeneous Muskat problem

Abstract

The inhomogeneous Muskat problem models the dynamics of an interface between two fluids of differing characteristics inside a nonuniform porous medium. We consider the case of a porous media with a permeability jump across a horizontal boundary away from an interface between two fluids of different viscosities and densities. For initial data of explicit medium size, depending on the characteristics of the fluids and porous media, we will prove the global existence and uniqueness of a solution that is instantly analytic and decays in time to the flat interface.