Automorphisms of Hyperkähler Manifolds in the View of Topological Entropy
نویسندگان
چکیده
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 nullentropy 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.
منابع مشابه
Groups of Automorphisms of Null-entropy of Hyperkähler Manifolds
The following two results are proven: The full automorphism group of any non-projective hyperkähler manifold M is almost abelian of rank at most maximum of ρ(M) − 1 and 1. Any groups of automorphisms of nullentropy of a projective hyperkähler manifold M is almost abelian of rank at most ρ(M) − 2. A few applications for K3 surfaces are also given.
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