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Actions of noncompact semisimple groups on Lorentz manifolds

Mohamed Deffaf·Karin Melnick·Abdelghani Zeghib
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Abstract

The above title is the same, but with "semisimple" instead of "simple," as that of a notice by N. Kowalsky. There, she announced many theorems on the subject of actions of simple Lie groups preserving a Lorentz structure. Unfortunately, she published proofs for essentially only half of the announced results before her premature death. Here, using a different, geometric approach, we generalize her results to the semisimple case, and give proofs of all her announced results.

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Mohamed Deffaf, Karin Melnick, Abdelghani Zeghib. 2007-04-05. Actions of noncompact semisimple groups on Lorentz manifolds. https://arxiv.org/abs/math/0601165

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