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arXiv · 2405.00501

Pseudo-Riemannian symmetric spaces of signature (2,2)

Ines Kath·Matti Lyko
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Abstract

We study all four-dimensional simply-connected indecomposable non-semisimple pseudo-Riemannian symmetric spaces whose metric has signature (2,2). We present models and compute their isometry groups. We solve the problem of the existence or non-existence of compact quotients by properly acting discrete subgroups of the isometry group. This continues and completes earlier work by Maeta.

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Ines Kath, Matti Lyko. 2026-07-13. Pseudo-Riemannian symmetric spaces of signature (2,2). https://doi.org/10.1007/s00031-025-09926-y

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