Combining Cauchy and characteristic codes. II. The interface problem for vacuum cylindrical symmetry.

Abstract

This paper continues a series investigating methods of combining Cauchy and characteristic techniques in numerical relativity. We present a technique for passing gravitational wave information between an inner Cauchy region and an outer, compactified, characteristic region via a numerical interface. In this developmental work the method is applied to vacuum cylindrical spacetime with two degrees of gravitational freedom. A comparison of our numerial results with an analytic solution, and a number of numerical experiments involving the propagation of Gaussian wave packets, indicate that the techniques presented here can produce very satisfactory results. \textcopyright{} 1995 The American Physical Society.