2 problems

Let $H$ be an analytic Hamiltonian system with an elliptic equilibrium point, having $n$ degrees of freedom. Assume that $n\geq 3$ and that the quadratic part of the Hamiltonian at…

Let $H$ be a real-analytic Hamiltonian with an elliptic equilibrium at the origin, and let $\alpha\in\mathbb R^n$ be the frequency vector of the linear part of the flow. Recall tha…