My research area is mathematical analysis, more precisely, theoretical aspects of nonlinear partial differential equations. The main focus is on regularity theory for a wide class of singular and degenerate elliptic and parabolic equations. These equations are connected to many different applications, such as diffusion in highly nonhomogeneous media and the motions of multiphased fluids in porous media. Methods from harmonic analysis are applied extensively and the research is also conducted in nonsmooth contexts, ultimately in metric measure spaces.