Discontinuous Galerkin (DG) methods coupled to WENO algorithms allow high
order convergence for smooth problems and for the simulation of discontinuities
and shocks. In this work, we investigate WENO-DG algorithms in the context of
numerical general relativity, in particular for general relativistic
hydrodynamics. We implement the standard WENO method at different orders, a
compact (simple) WENO scheme, as well as an alternative subcell evolution
algorithm. To evaluate the performance of the different numerical schemes, we
study non-relativistic, special relativistic, and general relativistic
testbeds. We present the first three-dimensional simulations of general
relativistic hydrodynamics, albeit for a fixed spacetime background, within the
framework of WENO-DG methods. The most important testbed is a single TOV-star
in three dimensions, showing that long term stable simulations of single
isolated neutron stars can be obtained with WENO-DG methods.Comment: 21 pages, 10 figure