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arXiv · 2302.02271

Dynamical degrees of automorphisms of complex simple abelian varieties and Salem numbers

Yutaro Sugimoto
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Abstract

We prove that every Salem number can be realized as the first dynamical degree of an automorphism of a complex simple abelian variety. Also by using the similar technique, we prove that the set of first dynamical degrees of automorphisms of complex simple abelian varieties except 1 has the minimum value when fixing the dimension of complex simple abelian varieties. Moreover, we prove that there is an automorphism of a complex simple abelian variety, whose first dynamical degree is as close as possible to 1. These results are inspired by the work of Nguyen-Bac Dang and Thorsten Herrig.

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Yutaro Sugimoto. 2023-02-05. Dynamical degrees of automorphisms of complex simple abelian varieties and Salem numbers. https://doi.org/10.1016/j.jalgebra.2025.06.009

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