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Cylindrical gravitational waves in expanding universes: Models for waves from compact sources

Robert H. Gowdy·B. Douglas Edmonds
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Abstract

New boundary conditions are imposed on the familiar cylindrical gravitational wave vacuum spacetimes. The new spacetime family represents cylindrical waves in a flat expanding (Kasner) universe. Space sections are flat and nonconical where the waves have not reached and wave amplitudes fall off more rapidly than they do in Einstein-Rosen solutions, permitting a more regular null inifinity.

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Robert H. Gowdy, B. Douglas Edmonds. 2007-04-06. Cylindrical gravitational waves in expanding universes: Models for waves from compact sources. https://doi.org/10.1103/physrevd.75.084011

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