Integrating post-Newtonian equations on graphics processing units

We report on early results of a numerical and statistical study of binary black hole inspirals. The two black holes are evolved using post-Newtonian approximations starting with initially randomly distributed spin vectors. We characterize certain aspects of the distribution shortly before merger. In particular we note the uniform distribution of black hole spin vector dot products shortly before merger and a high correlation between the initial and final black hole spin vector dot products in the equal-mass, maximally spinning case. More than 300 million simulations were performed on graphics processing units, and we demonstrate a speed-up of a factor 50 over a more conventional CPU implementation.