Numerical methods for changing type systems
  In this note we develop a numerical method for partial differential equations with changing type. Our method is based on a unified solution theory found by Rainer Picard for several linear equations from mathematical physics. Parallel to the solution theory already developed, we frame our numerical method in a discontinuous Galerkin approach in space-time with certain exponentially weighted spaces. 
Sebastian Franz, Sascha Trostorff and Marcus Waurick
math.NA