  We present self-consistent general relativistic simulations of stellar core
collapse, bounce, and postbounce evolution for 13, 15, and 20 solar mass
progenitors in spherical symmetry. Our simulations implement three-flavor
Boltzmann neutrino transport and standard nuclear physics. The results are
compared to our corresponding simulations with Newtonian hydrodynamics and
O(v/c) Boltzmann transport.
