S-arithmeticity of Discrete Subgroups Containing Lattices in Horospherical Subgroups
نویسنده
چکیده
0. Introduction. Let Qp be the field of p-adic numbers, and let Q∞ = R. Let Gp be a connected semisimpleQp-algebraic group. The unipotent radical of a proper parabolic Qp-subgroup of Gp is called a horospherical subgroup. Two horospherical subgroups are called opposite if they are the unipotent radicals of two opposite parabolic subgroups. In [5] and [6], we studied discrete subgroups generated by lattices in two opposite horospherical subgroups in a simple real algebraic group with real rank at least 2. This work was inspired by the following conjecture posed by G. Margulis.
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On Discrete Subgroups Containing a Lattice in a Horospherical Subgroup
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