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Refractive gravitational waves and quantum fluctuations

John W. Barrett
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Abstract

Refractive gravitational waves are a generalisation of impulsive waves on a null hypersurface in which the metric is discontinuous but a weaker continuity condition for areas holds. A simple example of a plane wave is examined in detail and two arguments are given that this should be considered a solution of Einstein's vacuum field equations. The study of these waves is motivated by quantum gravity, where the refractive plane waves are considered as elementary quantum fluctuations and the `area geometry' of a null hypersurface plays a primary role.

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John W. Barrett. 2000-11-14. Refractive gravitational waves and quantum fluctuations. https://arxiv.org/abs/gr-qc/0011051

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