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Cauchy-characteristic matching for a family of cylindrical vacuum solutions possessing both gravitational degrees of freedom

R. A. d'Inverno·M. R. Dubal·E. A. Sarkies
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Abstract

This paper is part of a long term program to Cauchy-characteristic matching (CCM) codes as investigative tools in numerical relativity. The approach has two distinct features: (i) it dispenses with an outer boundary condition and replaces this with matching conditions at an interface between the Cauchy and characteristic regions, and (ii) by employing a compactified coordinate, it proves possible to generate global solutions. In this paper CCM is applied to an exact two-parameter family of cylindrically symmetric vacuum solutions possessing both gravitational degrees of freedom due to Piran, Safier and Katz. This requires a modification of the previously constructed CCM cylindrical code because, even after using Geroch decomposition to factor out the $z$-direction, the family is not asymptotically flat. The key equations in the characteristic regime turn out to be regular singular in nature.

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R. A. d'Inverno, M. R. Dubal, E. A. Sarkies. 2000-02-16. Cauchy-characteristic matching for a family of cylindrical vacuum solutions possessing both gravitational degrees of freedom. https://doi.org/10.1088/0264-9381%2F17%2F16%2F305

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