On the Size of Quadratic Siegel Disks: Part I

dc.creatorBuff, Xavier
dc.creatorCheritat, Arnaud
dc.date2003-05-05
dc.date.accessioned2026-07-07T04:57:46Z
dc.date.available2026-07-07T04:57:46Z
dc.descriptionIf $\a$ is an irrational number, we let $\{p_n/q_n\}_{n\geq 0}$, be the approximants given by its continued fraction expansion. The Bruno series $B(\a)$ is defined as $$B(\a)=\sum_{n\geq 0} \frac{\log q_{n+1}}{q_n}.$$ The quadratic polynomial $P_\a:z\mapsto e^{2iπ\a}z+z^2$ has an indifferent fixed point at the origin. If $P_\a$ is linearizable, we let $r(\a)$ be the conformal radius of the Siegel disk and we set $r(\a)=0$ otherwise. Yoccoz proved that if $B(\a)=\infty$, then $r(\a)=0$ and $P_\a$ is not linearizable. In this article, we present a different proof and we show that there exists a constant $C$ such that for all irrational number $\a$ with $B(\a)<\infty$, we have $$B(\a)+\log r(\a) < C.$$ Together with former results of Yoccoz (see \cite{y}), this proves the conjectured boundedness of $B(\a)+\log r(\a)$.
dc.description22 pages, 4 figures
dc.identifierhttps://arxiv.org/abs/math/0305080
dc.identifierhttp://arxiv.org/abs/math/0305080
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/67377
dc.subjectDynamical Systems
dc.titleOn the Size of Quadratic Siegel Disks: Part I
dc.typetext

Files

Collections