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arXiv · 2210.12946

Lattice isometries and K3 surface automorphisms: Salem numbers of degree 20

Yuta Takada
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Abstract

This article extends Bayer-Fluckiger's theorem on characteristic polynomials of isometries on an even unimodular lattice to the case where the isometries have determinant $-1$. As an application, we show that the logarithm of every Salem number of degree $20$ is realized as the topological entropy of an automorphism of a nonprojective K3 surface.

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Yuta Takada. 2022-10-24. Lattice isometries and K3 surface automorphisms: Salem numbers of degree 20. https://arxiv.org/abs/2210.12946

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