Numerical relativity in Japan

〜1980: Nakamura, Maeda, Miyama & Sasaki

     2D, axisymetric collapse of a rotating star

the late 1980's: Nakamura, K.O. & Shibata
     3D numerical relativity (coalescing NS binaries)

〜1990: a post-Newtonian code

     100 CPU hours for each parameter set
     on a (3GFLOPS / 0.5GBytes) computer

1994〜: a full GR code
     a (〜100GFLOPS / 20GBytes) computer