Malnormal Subgroups of Lattices and the Pukánszky Invariant in Group Factors
نویسنده
چکیده
Let G be a connected semisimple real algebraic group. Assume that G(R) has no compact factors and let Γ be a torsionfree uniform lattice subgroup of G(R). Then Γ contains a malnormal abelian subgroup A. This implies that the II1 factor VN(Γ) contains a masa A with Pukánszky invariant {∞}.
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تاریخ انتشار 2009