Median Structures on Asymptotic Cones and Homomorphisms into Mapping Class Groups
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چکیده
We prove that every asymptotic cone of a mapping class group has a bi-Lipschitz equivariant embedding into a product of real trees, with image a median subspace. We deduce several applications of this, one of which is that a group with Kazhdan’s property (T) can only have finitely many pairwise non-conjugate homomorphisms into a mapping class group.
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تاریخ انتشار 2009