Scalar gravitation: A laboratory for numerical relativity. II. Disks

While not a correct physical theory, relativistic scalar gravitation provides a simple test site for developing many of the tools of numerical relativity. Using this theory, we have built a mean-field particle simulation scheme to study the dynamical behavior of collisionless disks. Disks are one-dimensional matter sources of two-dimensional gravitational fields. One-dimensional disk sources can be evolved without excessive computational resources and yet they are able to generate nonspherical gravitational waves. We find that we are able to calculate smooth and accurate wave forms from time-varying disks, despite the stochastic representation of the matter source terms caused by sampling with a finite number of particles. A similar scheme should provide accurate wave forms in general relativity, provided sufficient computer resources are used.