# On the topology of nearly-integrable Hamiltonians at simple resonances

@article{Biasco2020OnTT, title={On the topology of nearly-integrable Hamiltonians at simple resonances}, author={Luca Biasco and Luigi Chierchia}, journal={Nonlinearity}, year={2020} }

We show that, in general, averaging at simple resonances a real--analytic, nearly--integrable Hamiltonian, one obtains a one--dimensional system with a cosine--like potential; ``in general'' means for a generic class of holomorphic perturbations and apart from a finite number of simple resonances with small Fourier modes;
``cosine--like'' means that the potential depends only on the resonant angle, with respect to which it is a Morse function with one maximum and one minimum. \\ Furthermore…

## 4 Citations

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