On a Problem concerning Arithmeticity of Discrete Groups Acting
نویسنده
چکیده
We discuss an open problem on the discreteness of subgroups of (SL2(R)) (n ≥ 2) generated by n linearly independent upper triangular matrices and n linearly independent lower triangular matrices. According to a conjecture by Margulis, only Hilbert modular groups can arise this way. The purpose of this note is to explain how this open problem is related to another conjecture on the orbit behavior of diagonal subgroups in the homogeneous space SLn(Z)\SLn(R).
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