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Penrose limits of homogeneous spaces

Simon Philip
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Abstract

We prove that the Penrose limit of a spacetime along a homogeneous geodesic is a homogeneous plane wave spacetime and that the Penrose limit of a reductive homogeneous spacetime along a homogeneous geodesic is a Cahen--Wallach space. We then consider several homogenous examples to show that these results are indeed sharp and conclude with a remark about the existence of null homogeneous geodesics.

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Simon Philip. 2004-05-26. Penrose limits of homogeneous spaces. https://doi.org/10.1016/j.geomphys.2005.08.002

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