Kazhdan groups with infinite outer automorphism group
Abstract
For each countable group Q we produce a short exact sequence 1 N G Q 1 where G is f.g. and has a graphical 16 presentation and N is f.g. and satisfies property T. As a consequence we produce a group N with property T such that (N) is infinite. Using the tools developed we are also able to produce examples of nonHopfian and non-coHopfian groups with property T. One of our main tools is the use of random groups to achieve certain properties.
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