TOPOLOGICAL METHODS IN THE INSTABILITY PROBLEM OF HAMILTONIAN SYSTEMS
TOPOLOGICAL METHODS IN THE INSTABILITY PROBLEM OF HAMILTONIAN SYSTEMS
复制标题
解决哈密尔顿系统不稳定性问题的拓扑方法
DOI:
10.3934/dcds.2006.14.295
复制
发表时间:
2005
影响因子:
1.1
通讯作者:
R. Llave
中科院分区:
文献类型:
--
作者:
M. Gidea;R. Llave
We use topological methods to investigate some recently proposed
mechanisms of instability (Arnol'd diffusion) in Hamiltonian
systems.
In these mechanisms, chains of heteroclinic connections between
whiskered tori are constructed, based on the existence of a
normally hyperbolic manifold $\Lambda$, so that: (a) the manifold
$\Lambda$ is covered rather densely by transitive tori (possibly
of different topology), (b) the manifolds $W^\s_\Lambda$,
$W^\u_\Lambda$ intersect transversally, (c) the systems satisfies
some explicit non-degeneracy assumptions, which hold generically.
In this paper we use the method of correctly aligned windows to
show that, under the assumptions (a), (b), (c), there are orbits
that move a significant amount.
As a matter of fact, the method presented here does not require
that the tori are exactly invariant, only that they are
approximately invariant. Hence, compared with the previous
papers, we do not need to use KAM theory. This lowers the
assumptions on differentiability.
Also, the method presented here allows us to produce concrete
estimates on the time to move, which were not considered in the
previous papers.