Lyapunov exponents in fundamental models of nonlinear resonance
I. I. Shevchenko
Saint Petersburg State University, 199034 St. Petersburg, Russia
Institute of Applied Astronomy, Russian Academy of Sciences, 191187 St. Petersburg, Russia
Abstract
The problem of analytical estimation of the Lyapunov exponents
and Lyapunov timescales of the motion in multiplets of interacting
nonlinear resonances is considered. To this end, we elaborate a unified
framework, based on the separatrix map theory, which incorporates
both an earlier approach for the first fundamental model of perturbed
resonance (given by the perturbed pendulum Hamiltonian) and a new
one for its second fundamental model (given by the perturbed Andoyer
Hamiltonian). Within this framework, new accurate estimates for the
Lyapunov timescales of the inner and outer subsystems of the Solar
planetary system are presented and discussed.