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arXiv · 1805.00045

Arithmeticity of discrete subgroups containing horospherical lattices

Yves Benoist·Sébastien Miquel
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Abstract

Let $G$ be a semisimple real algebraic Lie group of real rank at least two and $U$ be the unipotent radical of a non-trivial parabolic subgroup. We prove that a discrete Zariski dense subgroup of $G$ that contains an irreducible lattice of $U$ is an arithmetic lattice of $G$. This solves a conjecture of Margulis and extends previous work of Hee Oh.

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Yves Benoist, Sébastien Miquel. 2018-04-30. Arithmeticity of discrete subgroups containing horospherical lattices. https://doi.org/10.1215/00127094-2019-0082

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