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arXiv · gr-qc/9804027

Godel metric as a squashed anti-de Sitter geometry

M. Rooman·Ph. Spindel
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Abstract

We show that the non flat factor of the Godel metric belongs to a one parameter family of 2+1 dimensional geometries that also includes the anti-de Sitter metric. The elements of this family allow a generalization a la Kaluza-Klein of the usual 3+1 dimensional Godel metric. Their lightcones can be viewed as deformations of the anti-de Sitter ones, involving tilting and squashing. This provides a simple geometric picture of the causal structure of these space-times, anti-de Sitter geometry appearing as the boundary between causally safe and causally pathological spaces. Furthermore, we construct a global algebraic isometric embedding of these metrics in 4+3 or 3+4 dimensional flat spaces, thereby illustrating in another way the occurrence of the closed timelike curves.

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M. Rooman, Ph. Spindel. 1998-06-30. Godel metric as a squashed anti-de Sitter geometry. https://doi.org/10.1088/0264-9381%2F15%2F10%2F024

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