论文标题
关于理性功能的迭代对称性
On symmetries of iterates of rational functions
论文作者
论文摘要
令$ a $是学位$ n \ geq 2 $的合理功能。让我们用$ g(a)$表示Möbius变换$σ$的组,以便$ a \circcσ=ν_σ\ circ a $对于某些möbius变换$ν_σ$,以及$σ(a)$ and $ {$和$ {\ rm aut}(a aut}(a)$ g(a)相应地,A \Circσ=σ\ Circ a $。在本文中,我们研究了以上$ a $ $ $的序列的序列。特别是,我们表明,如果$ a $与$ z^{\ pm n},$,那么$ g(a^{\ circ k})$,$ k \ geq 2的订单,$是有限的,均为有限的,仅以$ n $ $ n $均匀限制。我们还证明了$σ_{\ infty}(a)= \ cup_ {k = 1}^{\ infty}σ(a^{\ circ k})$和$ {\ rm aut} _ {\ rm aut} _ { aut}(a^{\ circ k})$,从动态角度来看,这特别有趣。
Let $A$ be a rational function of degree $n\geq 2$. Let us denote by $ G(A)$ the group of Möbius transformations $σ$ such that $ A\circ σ=ν_σ \circ A$ for some Möbius transformations $ν_σ$, and by $Σ(A)$ and ${\rm Aut}(A)$ the subgroups of $ G(A)$ consisting of $σ$ such that $ A\circ σ= A$ and $ A\circ σ= σ\circ A$, correspondingly. In this paper, we study sequences of the above groups arising from iterating $A$. In particular, we show that if $A$ is not conjugate to $z^{\pm n},$ then the orders of the groups $ G(A^{\circ k})$, $k\geq 2,$ are finite and uniformly bounded in terms of $n$ only. We also prove a number of results about the groups $Σ_{\infty}(A)=\cup_{k=1}^{\infty} Σ(A^{\circ k})$ and ${\rm Aut}_{\infty}(A)=\cup_{k=1}^{\infty} {\rm Aut}(A^{\circ k})$, which are especially interesting from the dynamical perspective.