We consider spherically symmetric, asymptotically flat space-times with a
collisionless gas as matter model. Many properties of the resulting
Vlasov-Einstein system are not yet accessible by purely analytical means. We
present a discretized version of this system which is suitable for numerical
implementation and is based on the particle-in-cell technique. Convergence of
the resulting approximate solutions to the exact solution is proven and error
bounds are provided.Comment: 38 page