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arXiv · 1912.01324

Dynamical degrees of affine-triangular automorphisms of affine spaces

Jérémy Blanc·Immanuel van Santen
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Abstract

We study the possible dynamical degrees of automorphisms of the affine space $\mathbb{A}^n$. In dimension $n=3$, we determine all dynamical degrees arising from the composition of an affine automorphism with a triangular one. This generalises the easier case of shift-like automorphisms which can be studied in any dimension. We also prove that each weak Perron number is the dynamical degree of an affine-triangular automorphism of the affine space $\mathbb{A}^n$ for some $n$, and we give the best possible $n$ for quadratic integers, which is either $3$ or $4$.

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Jérémy Blanc, Immanuel van Santen. 2019-12-03. Dynamical degrees of affine-triangular automorphisms of affine spaces. https://arxiv.org/abs/1912.01324

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