After that, we turn to modern applications this theory. First, we build the important for mathematics and mathematical physics еруKadomtsev -Petviashvili  hierarchy  and use proved above resalts to construct important solutions of this differential equations. Then we use the theory of harmonic functions and the theory of differential hierarchies for  explicitly construct a conformally  mapping that translates an arbitrary contractible domain into a standard disk. This classical problem has important applications in hydrodynamics, gas dynamics, etc. weiterlesen