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arXiv · 2110.04213

Invariant measures for large automorphism groups of projective surfaces

Serge Cantat·Romain Dujardin
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Abstract

We classify invariant probability measures for non-elementary groups of automorphisms, on any compact K\"ahler surface X, under the assumption that the group contains a so-called "parabolic automorphism". We also prove that except in certain rigid situations known as Kummer examples, there are only finitely many invariant, ergodic, probability measures with a Zariski dense support. If X is a K3 or Enriques surface, and the group does not preserve any algebraic subset, this leads to a complete description of orbit closures.

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Serge Cantat, Romain Dujardin. 2021-10-08. Invariant measures for large automorphism groups of projective surfaces. https://arxiv.org/abs/2110.04213

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