# Paper on Discontinuous Galerkin methods with Trefftz approximations published in JCAM

Fritz Kretzschmar, Igor Tsukerman and I have a new paper in Journal of Computational Applied Mathematics (JCAM). The paper abstract reads

We present a novel Discontinuous Galerkin Finite Element Method for wave propagation problems. The method employs space–time Trefftz-type basis functions that satisfy the underlying partial differential equations and the respective interface boundary conditions exactly in an element-wise fashion. The basis functions can be of arbitrary high order, and we demonstrate spectral convergence in the $$L_2$$-norm. In this context, spectral convergence is obtained with respect to the approximation error in the entire space–time domain of interest, i.e. in space and time simultaneously. Formulating the approximation in terms of a space–time Trefftz basis makes high order time integration an inherent property of the method and clearly sets it apart from methods, that employ a high order approximation in space only.