Integration of inhomogeneous cosmological spacetimes in the BSSN
  formalism
  We present cosmological-scale numerical simulations of an evolving universe
in full general relativity (GR) and introduce a new numerical tool, {\sc
CosmoGRaPH}, which employs the Baumgarte-Shapiro-Shibata-Nakamura (BSSN)
formalism on a 3-dimensional grid. Using {\sc CosmoGRaPH}, we calculate the
effect of an inhomogeneous matter distribution on the evolution of a spacetime.
We also present the results of a set of standard stability tests to demonstrate
the robustness of our simulations.
