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Interpretation of the Siklos solutions as exact gravitational waves in the anti-de Sitter universe

J. Podolsky
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Abstract

The Siklos class of solutions of Einstein's field equations is investigated by analytical methods. By studying the behaviour of free particles we reach the conclusion that the space-times represent exact gravitational waves propagating in the anti-de Sitter universe. The presence of a negative cosmological constant implies that the 'background' space is not asymptotically flat and requires a 'rotating' reference frames in order to fully simplify and view the behaviour of nearby test particles. The Kaigorodov space-time, which is the simplest representative of the Siklos class, is analyzed in more detail. It is argued that it may serve as a 'cosmological' analogue of the well-known homogeneous pp-waves in the flat universe.

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J. Podolsky. 1998-01-15. Interpretation of the Siklos solutions as exact gravitational waves in the anti-de Sitter universe. https://doi.org/10.1088/0264-9381%2F15%2F3%2F019

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