Automorphisms of non-spherical buildings have unbounded displacement

Peter Abramenko; Kenneth S. Brown

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arXiv · 0710.1426

Automorphisms of non-spherical buildings have unbounded displacement

Peter Abramenko·Kenneth S. Brown

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Abstract

If f is a nontrivial automorphism of a thick building Delta of purely infinite type, we prove that there is no bound on the distance that f moves a chamber. This has the following group-theoretic consequence: If G is a group of automorphisms of Delta with bounded quotient, then the center of G is trivial.

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Peter Abramenko, Kenneth S. Brown. 2007-10-07. Automorphisms of non-spherical buildings have unbounded displacement. https://arxiv.org/abs/0710.1426

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