Note: When clicking on a Digital Object Identifier (DOI) number, you will be taken to an external site maintained by the publisher.
Some full text articles may not yet be available without a charge during the embargo (administrative interval).
What is a DOI Number?
Some links on this page may take you to non-federal websites. Their policies may differ from this site.
-
Abstract Consider an analytic Hamiltonian system near its analytic invariant torus $\mathcal T_0$ carrying zero frequency. We assume that the Birkhoff normal form of the Hamiltonian at $\mathcal T_0$ is convergent and has a particular form: it is an analytic function of its non-degenerate quadratic part. We prove that in this case there is an analytic canonical transformation—not just a formal power series—bringing the Hamiltonian into its Birkhoff normal form.more » « less
-
Any
conservative map\begin{document}$ C^d $\end{document} of the\begin{document}$ f $\end{document} -dimensional unit ball\begin{document}$ d $\end{document} ,\begin{document}$ {\mathbb B}^d $\end{document} , can be realized by renormalized iteration of a\begin{document}$ d\geq 2 $\end{document} perturbation of identity: there exists a conservative diffeomorphism of\begin{document}$ C^d $\end{document} , arbitrarily close to identity in the\begin{document}$ {\mathbb B}^d $\end{document} topology, that has a periodic disc on which the return dynamics after a\begin{document}$ C^d $\end{document} change of coordinates is exactly\begin{document}$ C^d $\end{document} .\begin{document}$ f $\end{document}