Relative Kazhdan Property
نویسنده
چکیده
We perform a systematic investigation of Kazhdan’s relative Property (T) for pairs (G,X), G a locally compact group and X any subset. When G is a connected Lie group or a p-adic algebraic group, we provide an explicit characterization of subsets X ⊂ G such that (G,X) has relative Property (T). In order to extend this characterization to lattices Γ ⊂ G, a notion of “resolutions” is introduced, and various characterizations of it are given. Special attention is paid to subgroups of SU(2, 1) and SO(4, 1).
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