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arXiv · 0707.2920

A non-homogeneous orbit of a diagonal subgroup

François Maucourant
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Abstract

Let G=SL(n,R) with n>5. We construct examples of lattices Gamma of G, subgroup A of the diagonal group and points x in G/Gamma such that the closure of the orbit Ax is not homogeneous but does not factors through the action of a one-parameter non-unipotent group. This contradicts a conjecture of Margulis.

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François Maucourant. 2008-08-28. A non-homogeneous orbit of a diagonal subgroup. https://arxiv.org/abs/0707.2920

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