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Junction Conditions of Friedmann-Robertson-Walker Space-Times

Nobuyuki Sakai·Kei-ichi Maeda
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Abstract

We complete a classification of junctions of two Friedmann-Robertson-Walker space-times bounded by a spherical thin wall. Our analysis covers super-horizon bubbles and thus complements the previous work of Berezin, Kuzumin and Tkachev. Contrary to sub-horizon bubbles, various topology types for super-horizon bubbles are possible, regardless of the sign of the extrinsic curvature. We also derive a formula for the peculiar velocity of a domain wall for all types of junction.

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Nobuyuki Sakai, Kei-ichi Maeda. 1994-08-04. Junction Conditions of Friedmann-Robertson-Walker Space-Times. https://doi.org/10.1103/physrevd.50.5425

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