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arXiv · 0711.2746

Actions of semisimple Lie groups preserving a degenerate Riemannian metric

Esmaa Bekkara·Charles Frances·Abdelghani Zeghib
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Abstract

We prove a rigidity of the lightcone in Minkowski space. It is essentially the unique space endowed with a degenerate Riemannian metric, of lightlike type, and supporting an isometric non-proper action of a semi-simple group.

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Esmaa Bekkara, Charles Frances, Abdelghani Zeghib. 2007-11-17. Actions of semisimple Lie groups preserving a degenerate Riemannian metric. https://arxiv.org/abs/0711.2746

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