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Automorphisms of hyperkähler manifolds in the view of topological entropy

Keiji Oguiso
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Abstract

First we show that any group of automorphisms of null-entropy of a projective hyperkähler manifold $M$ is almost abelian of rank at most $ρ(M) - 2$. We then characterize automorphisms of a K3 surface with null-entropy and those with positive entropy in algebro-geometric terms. We also give an example of a group of automorphisms which is not almost abelian in each dimension.

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Keiji Oguiso. 2005-04-25. Automorphisms of hyperkähler manifolds in the view of topological entropy. https://arxiv.org/abs/math/0407476

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