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arXiv · 2107.07583

Isometries of lattices and automorphisms of K3 surfaces

Eva Bayer-Fluckiger
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Abstract

The aim of this paper is to give necessary and sufficient conditions for an integral polynomial to be the characteristic polynomial of a semi-simple isometry of some even unimodular lattice of given signature. This result has applications applications to automorphisms of K3 surfaces; in particular, we show that every Salem number of degree 4, 6, 8,1 2, 14 or 16 is the dynamical degree of an automorphism of a non-projective K3 surface.

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Eva Bayer-Fluckiger. 2021-07-15. Isometries of lattices and automorphisms of K3 surfaces. https://arxiv.org/abs/2107.07583

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