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Junctions and thin shells in general relativity using computer algebra I: The Darmois-Israel Formalism

P. Musgrave·K. Lake
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Abstract

We present the GRjunction package which allows boundary surfaces and thin-shells in general relativity to be studied with a computer algebra system. Implementing the Darmois-Israel thin shell formalism requires a careful selection of definitions and algorithms to ensure that results are generated in a straight-forward way. We have used the package to correctly reproduce a wide variety of examples from the literature. We present several of these verifications as a means of demonstrating the packages capabilities. We then use GRjunction to perform a new calculation - joining two Kerr solutions with differing masses and angular momenta along a thin shell in the slow rotation limit.

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P. Musgrave, K. Lake. 1995-12-11. Junctions and thin shells in general relativity using computer algebra I: The Darmois-Israel Formalism. https://doi.org/10.1088/0264-9381%2F13%2F7%2F018

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