English

Generically, Arnold-Liouville Systems Cannot be Bi-Hamiltonian

Differential Geometry 2021-11-01 v2

Abstract

We state and prove that a certain class of smooth functions said to be BH-separable is a meagre subset for the Fr\'echet topology. Because these functions are the only admissible Hamiltonians for Arnold-Liouville systems admitting a bi-Hamiltonian structure, we get that, generically, Arnold-Liouville systems cannot be bi-Hamiltonian. At the end of the paper, we determine, both as a concrete representation of our general result and as an illustrative list, which polynomial Hamiltonians HH of the form H(x,y)=xy+ax3+bx2y+cxy2+dy3H(x,y)=xy+ax^3+bx^2y+cxy^2+dy^3 are BH-separable.

Cite

@article{arxiv.2105.11123,
  title  = {Generically, Arnold-Liouville Systems Cannot be Bi-Hamiltonian},
  author = {Hassan Boualem and Robert Brouzet},
  journal= {arXiv preprint arXiv:2105.11123},
  year   = {2021}
}
R2 v1 2026-06-24T02:23:49.255Z