On the optimal effective stability bounds for quasi-periodic tori of finitely differentiable and Gevrey Hamiltonians

It is known that a Diophantine quasi-periodic torus with frequency ω∈Ωτd of a Cl Hamiltonian is effectively stable for a time T(r) that is polynomial on the inverse of the distance to the torus, that we denote by r, with exponent 1 + (l- 2) / (τ+ 1) . It is also known that a Diophantine quasi-period...

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Detalles Bibliográficos
Autor: Farré, G.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2023
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2072/537445
Acceso en línea:http://hdl.handle.net/2072/537445
Access Level:acceso abierto
Palabra clave:Effective stability
Hamiltonian systems
Quasi-periodic tori
Descripción
Sumario:It is known that a Diophantine quasi-periodic torus with frequency ω∈Ωτd of a Cl Hamiltonian is effectively stable for a time T(r) that is polynomial on the inverse of the distance to the torus, that we denote by r, with exponent 1 + (l- 2) / (τ+ 1) . It is also known that a Diophantine quasi-periodic torus of a Gevrey Hamiltonian H∈ Gα,L is effectively stable for an exponentially long time on the inverse of the distance to the torus with exponent 1 / (α(1 + τ)) . In this note, we see that following the methods in [11] one can show the almost optimality of these exponents. We also show that, for a dense subset of non-resonant vectors, for quasi-periodic tori of finitely differentiable and Gevrey Hamiltonians, the naive lower bound T(r) ≥ Cr- 1 is optimal in terms of the exponent. © 2023, The Author(s).